The casting of Jodie Whittaker as the lead in Doctor Who is the difference between tolerating modernity and embodying it – but why has it taken so long to get here?

The announcement of the first female Doctor felt almost Whovian in its unfolding. The men’s singles final at Wimbledon had just finished, the nation having been primed for two weeks with hour upon hour of a sporting event mainly about – for people not interested in hand-eye coordination – Britishness and gender. We were, therefore, in the right psychic space to go bananas, and we duly did. A little girl reacted on Twitter with wonderment and joy. At the same time, a coordinated warrior army of creatures born to hate, whose only thought was to destroy those not like them – similar to the Daleks, not wishing to labour the point – arrived to decry the decision. This was it, the giddy limit, the moment they stopped watching, the endpoint of political correctness. A female Doctor. Why a doctor at all? Why not a separate show called Nurse Who? Why do liberals have to take everything they love and ruin it? Is nothing sacred?

An immortal time traveller with two hearts who persistently defies the laws of physics – that they could handle. But break the laws of the patriarchy, in which men alone get to do derring? No way. There was almost more enjoyment in defending the casting of Jodie Whittaker than there was in the glittering moment of discovery. A surge of playfulness, from people whom I hazard have watched, but rarely understood, an episode of Doctor Who (not because you have to be sexist to understand it, just because it is incomprehensible), brought the progressive online carnival to a crescendo. First the general election, now this. Sometimes things have to start going your way before you realise how bad they were.

We take it seriously when a mainstream show, especially one for children, breaks a cultural taboo, and rightly so: you can evolve as far as you like towards diversity and pluralism in the worlds of poetry or sociology, but if you don’t bring those values into the living room – particularly for a Christmas special, a cultural mop-up that catches impressionable, young minds and bigoted, old drunks at once – you will always be niche, ignorable, contestable. Appearing as the Doctor is the definition of acceptability; people are still free to grumble, but from that point on it is they who are on the outside, looking in.

The programme has always taken this power admirably seriously: more than a decade ago, they introduced an omnisexual time traveller, Captain Jack Harkness, the show’s first non-heterosexual character. The bigger deal, though, was that he was sexually voracious. The normal convention for the nursery slopes of sexual diversity is that if you are not interested in straight sex, you have to be ambivalent about the whole business. In 2012, the Doctor’s companion Clara was the show’s first bisexual woman; in 2017 came Bill Potts, its first gay, working-class person of colour, who was also a pilot. But peopling the support cast with greater diversity is a way off casting Whittaker in the lead role; a female Doctor is the watermark of gender blindness, the difference between tolerating modernity and embodying it.

The paradox of entertainment is that modern values take so long to catch on. The ultimate showbiz character is liberal, creative, mould-breaking, forward-thinking, highly unlikely to be bound by conservative and/or religious values. Showbiz is a world for misfits, not rule-followers. Yet nowhere do we see a plainer iteration of “traditional” thinking than on our screens. It is more surprising to find a woman in a blockbuster movie with a mind of her own than it is to find a woman in an “arthouse” film not naked or crying. It is more likely for a 10-part thriller to start with a dead woman’s body than a living woman expressing agency and determination. It is routine for a current affairs team to be led by a grey-haired man doing the serious stories while a fit, younger woman handles the family stuff. Important political events, be they regular (Question Time) or irregular (general elections), are seen as male territory by default, women seemingly included under sufferance. Panel shows shoehorn in a woman to salve their consciences; women can exist, but never get old, on nature shows. Black actors have a more arduous trajectory still, sometimes having to go to the US and make it big before they are considered famous enough to overcome the tacit colour bar in the UK.

Facebook Twitter Pinterest The omnisexual time traveller who proved so popular that he got his own spinoff show ... John Barrowman as Captain Jack Harkness. Photograph: Steve Brown/BBC Worldwide

The extraordinarily slow pace of change is a sharp contrast to the good game everyone talks. TV executives constantly underline their commitment to equality, while happily accepting that men must keep the main jobs until they are literally dead. Meanwhile, in fields considered naturally more conservative – policing, law, accountancy, government – women and people of colour, while still underrepresented, can make it to the top; there is broad acceptance that scrutiny is welcomed and male dominance unwanted.

It is the stasis that baffles. How is it possible for such a visible industry to stay for so long in a male-dominated, monochrome world that it often decries explicitly? Take the dynamics of the blockbuster, the raison d’etre of which is to appeal to the widest audience possible. A white, male protagonist adhering to classical heroic ideals is point zero, the character everyone understands and from whom no one recoils. If you lose only five viewers by giving him one unexpected trait – long hair, a third nipple – they are viewers you need not have lost. Sometimes those five are taken as collateral damage for giving the film some edge, but too much edge is money down the drain.

This is observable in women’s magazines, too. The assumption is that featuring a person of colour on the cover will mean selling fewer copies. Conveniently, it has been shown that the perception of beauty is colourblind, that racism is not hardwired into our evolutionary pathway; indeed, the opposite is true – genetic diversity is a boon to survival. When you try to commodify beauty, however, a sociological Fordism intervenes: any colour, so long as it is white. The easiest way to serve a mass market is with identikit heroes.

The upshot is far more serious than a failure to reflect a changing world: culture that has its business model pegged to homogeneity reinforces and polices a world order in which everyone is the same age, the same sex and the same colour – and in which all admirable traits remain locked in that shape.

In an ideal world, public-service broadcasting would be free from the constraints of mass production; it is not there for profit and should not have to worry about splitting the crowd. This has always been a conundrum for the BBC, which has its Reithian principles – to inform, to educate and to entertain – but no way of measuring its success beyond viewing figures and bare assertion. So, it is locked in the same value structure as its competitors, attempting to create the product most digestible by the largest possible audience.

Perhaps the most extraordinary thing about this is that it locks the BBC into tropes that you would not, from a standing start, deem crowd-pleasing. Who would think that a dancing contest would be best moderated by an 80-year-old? Why does a joke have to be told, or a current-affairs interview conducted, by a man?

Facebook Twitter Pinterest The 12th Doctor (Peter Capaldi) with Bill Potts (Pearl Mackie), the show’s first gay, working-class person of colour. Photograph: Ray Burmiston/BBC

Stuck in the values of a vanished world order, its editorial decisions have started to look almost quirkily out of kilter with the regular world. But the BBC’s audience continues to accept this – authority in the male, frippery in the female, trustworthiness in the Caucasian, funkiness in the foreign – as normal. The depressing reading is that, in maintaining this ossified vision of what normal should look like, the BBC has not only obstructed progress in the past, but also affiliated to this profile all its lauded virtues, meaning intelligence, challenge, social ease, charisma, quick thinking, humour, bravery and time travel can come only from a male hero. If true, this would be worse than failing to dispatch a public service: it would make the BBC a public-disservice broadcaster.

I was the Doctor and I’m over the moon that at last we have a female lead | Colin Baker Read more

So, that is the depressing reading. In fact, I think the timorous mainstream merely underestimates its audience. We do not need a Dimbleby before we can appreciate seriousness, or knockout cheekbones before we can understand what a woman is doing onscreen. We put up with such protocols while we wait for better ones.

The female Doctor is part of a revolutionary feminist triptych, the other two being the female superhero (Wonder Woman) and the female Bond (the forthcoming Rhythm Section, directed by Reed Morano, is about a spy who is basically Bond in every respect, except that she is not called Bond). Wonder Woman is the only one we can judge at this stage, and reflect on how much these moments do for equality, beyond simply putting a woman front and centre. Once you do that, other canards around femininity fall like dominoes. Before you know it, you have a heroine who is not only preternaturally strong, but also can talk. Whittaker’s inauguration is only the beginning. It is exhilarating to think how many cliches a woman in this role will tear down.