“Another day, yet another newspaper critic in @ThatTimWalker faces the axe,” the Tricycle Theatre in north London tweeted recently, when it was announced the curtain was coming down on my run as the Sunday Telegraph’s chief theatre critic. “What’s going on? Theatre will be the poorer without these voices.”

The great director Michael Grandage, along with Bill Kenwright’s company, Sir Howard Panter’s Ambassador Theatre Group and Jamie Lloyd’s Trafalgar Studios, among many others, retweeted this howl of despair – and one can well understand it.

Agree with my reviews or not – and, goodness knows, a lot of people certainly didn’t in the early days when I was known as The Critic They Love to Hate – but at least I turned up with my notebook for the first nights. Now, all too often, the seats in the stalls where my colleagues and I used to sit are being left vacant.

My decade doing the job coincided with a bloodbath among my fraternity that has been every bit as savage and indiscriminate as the one that was perpetrated by Vincent Price in that splendid 70s shocker Theatre of Blood. Among the biggest names I saw bumped off were Michael Portillo (the New Statesman), Libby Purves (the Times) and Nicholas de Jongh (the London Evening Standard).

Entire review sections – especially on the Sundays – have been shut down, arts budgets are being slashed, and the critics that are still standing are having to pick and choose between productions because they cannot physically get to them all.

Theatres outside the capital are now finding the only way they can ensure that certain critics show up for their first nights is for them to pay for travel and accommodation (which puts some of my old colleagues into an ethically dodgy position: is the cost of a five-star review now a five-star hotel?).

One leading impresario told me he looked around at the motley crowd that had turned up to sit in judgment on one of his productions and he realised he didn’t know a single one of them. “They were young, spotty, out of their comfort zones and clearly exhausted, having been diverted at the last minute from other tasks at their hard-pressed media organisations,” he lamented. “Honestly, after all the work we had put in on our side, and all the investment, it felt like a slap in the face.”

Theatre director Michael Grandage said theatre should never end when the curtain comes down. Photograph: Sarah Lee

The conventional wisdom is that readers of theatre reviews are migrating – along with the advertising – to online, but who, honestly, can name an internet critic who has the authority of, say, the Guardian’s Michael Billington? Or – until he also joined the exodus – the Telegraph’s Charles Spencer?

A lot of prospective theatre-goers do, of course, read the verdicts of the newspaper critics online, but the point is they still gravitate towards the brand names they feel most comfortable with, such as the Guardian, the Telegraph, or indeed the Mail, which, commendably, still takes theatre criticism seriously and resources it properly.

And walk up Shaftesbury Avenue and you will see it is still the words of the newspaper critics – rather than anyone from the blogosphere – which are quoted on the hoardings outside the big playhouses. The fact is the serious newspapers and the theatres have the perfect relationship because the demographics of their respective clients are pretty much identical: middle-class, affluent, and, of course, getting on a bit.

In recent years, the fortunes of newspapers and theatres have, of course, headed in starkly different directions, with the former entering a period of rapid decline, and the latter – so far as the West End is concerned – going from strength to strength as it reliably reports revenues of around half a billion every year.

Theatre managements cutting back on their print advertisements – and newspapers that are, as a direct consequence, dispensing with their critics – form a vicious circle that is, to all intents and purposes, silencing an enriching and time-honoured conversation that Agate and Tynan – and more recently Billington and Spencer – have contributed to with such insight and style. As Grandage told me, theatre should never end when the curtain comes down: that is the moment when, in many respects, the important part begins and the discussion about what has just been played out really commences.

Sadly, I just don’t see that conversation – led so confidently by the newspaper critics for so long – being continued in any serious form online or anywhere else, for that matter, in the future. Certainly, if there are any Angry Young Men out there now preparing to make their entrances, they had better be quick about it, otherwise I wonder who on earth will still be around to recognise them, still less have the space to record their triumphs for posterity.