I am a person who debates in public. Debate is good, debate is healthy. We can disagree. We can disagree and still love each other. Unless, as the blogger Son of Baldwin said, your disagreement is rooted in my oppression, your denial of my humanity, my right to exist.

A reminder of this most salient quote is one of almost 100,000 responses I received to a video I shared on social media a few days ago, which has subsequently been viewed 3 million times. The very public and communal way it has been consumed online is in perfect contrast to the very private and lonely way it was created. By me, sitting in a room, with colleagues on a Sky News debate show, who wanted to argue about an image that compared the newborn child of the Duke and Duchess of Sussex to a chimp, and the consequences for the person who posted it.

I was not performing, I was living another traumatic encounter with the denial of my experience

The image in question has received widespread and exhaustive media attention. But even as public discourse in Britain has managed to achieve a level of nuance in the discussion of race and identity, here was an instantly recognisable trope, familiar to generations of black people, shared on the birth of a baby whose family includes an African American grandmother, by someone paid by the BBC. That there was widespread condemnation of its racist nature – including from the man who posted it – is one of many reasons I was exasperated at having to debate it.

I wish I could say that since I am resilient (I am), that since I am comfortable, as a former barrister, with adversarial conversations (I am), that since I have done the work as an author to equip myself to engage in discourse about racism and identity (I have), that encounters like this therefore do not affect me deeply. But they do.

The reality is that while the other panellists walked away, another job done, their place in the world or sense of their own humanity unscathed, and the programme’s production team congratulated me on a “strong” performance, I was not performing. I was living another traumatic encounter with the denial of my experience. I was carrying a burden for all people of colour who have to carry out their professional duties while being dehumanised. I was telling myself how few spaces there are for us in the mainstream media to communicate this experience, feeling all the pressure of doing us justice that entails. I was depressed that, even if my anger might have woken people up temporarily, nothing would actually change.

And the reason I was visibly raging in this instance, was because I realised, on air, that I had had enough – not just of having to deal with the content of an idea that compares people like me to another species, but of then being expected to persuade people why that’s bad.

Because this emotional labour is not distributed equally, broadcasters – by placing one black person in a hostile space and then requiring them to explain the injustice of racism – become complicit in that injustice. They may feel their complicity is rewarded by the viral nature of the response.

But if you read the messages from the thousands of people who reacted to my experience, they were not praising the programme, as people often do when they watch something they relate to, and they were not expressing any enjoyment in watching it. They were overwhelmingly excoriating the show for putting me in a position of having to argue something they found unnecessary to explain, painful to watch and similarly traumatic to relate to.

Afua Hirsch (@afuahirsch) I’m not doing this again pic.twitter.com/93jILnHxWk

The scale of this communal sense of injury gave me the impression that people of colour in Britain are nursing something of a collective wound. My latest experience – I have both been here, and written about being here, before – took place just as the Guardian reported on new figures on the scale of racism in Britain, post-Brexit.

An Opinium poll has found that the proportion of British people from an ethnic minority who have been targeted with racist abuse by a stranger rose from 64% three years ago to 76% this year. It’s as if the private versions of this encounter lived by people up and down this country, accumulating over time, have become a scab that is ripped off by witnessing a similar incident playing out in the public form of a TV debate.

If we are bleeding en masse, we are doing so at a time when the spotlight is firmly upon the ways in which broadcasters are incentivised to create conflict. The suicides of participants on the Jeremy Kyle show, and of former contestants on Love Island, have prompted fresh debates about the exploitative nature of reality TV. Current affairs debate shows are different – at least I have always thought of them as different – because on the whole they rely on participants discussing matters that are separate from their personal lives – the Brexit withdrawal agreement, say, or nationalisation of the railways. But race is a topic on shows such as the one I am in almost every week, almost never introduced by me. There is now an implicit understanding that panels discussing such issues should be “diverse”, that is to say, should include one person who is racialised as something other than white. Being not white becomes that person’s role, their personal experiences of being racialised have been commoditised into a necessary part of the output.

Perhaps this explains why the instinct of so many people on social media who saw this clip was to recognise that exploitation; to regard it as an assault on my mental wellbeing just as it would be for theirs. The link between experiences of racism and mental health is becoming better understood, out of necessity, in making sense of why it is that black people suffer from among the highest rates of anxiety and depression of any group in the UK.

Many believe this reality is linked to the exhaustion of experiencing and responding to racism, the “weight of representing your race”, of “policing your behaviour and diminishing your authentic self so that others feel at ease in your presence”, and then – to top it all off – the fear that expressing your refusal to tolerate that catastrophic mix will see you labelled an angry black woman.

The good news is that our tolerance threshold has been breached. If I left the TV studio last week feeling drained and alone, I soon felt surrounded by enthusiastic love from people of all races. Among the brilliant responses to the clip of my suffering was one from the former deputy mayor of London Matthew Ryder who posted an image from the movie Black Panther of Wakanda warriors ready for battle, as a metaphor for the solidarity I was shown by black Twitter.

If TV imitates life, I once felt defeated by the precariousness of debates like this. Now I – and so many of us out there – use it to build defiance. We do that not because of those who put us in this position in the first place, but in spite of them.

• Afua Hirsch is a Guardian columnist

• This article was amended on 23 May 2019. An earlier version attributed a quote to the American author James Baldwin which actually came from the contemporary writer Robert Jones Jr, who tweets as Son of Baldwin.