The Sunday Times TV critic AA Gill refers to his girlfriend as "The Blonde", nothing more. I have idly wondered in the past why he chooses to describe her like this in his columns. Perhaps, because in our society, and particularly in the world of male one-upmanship, "blonde" has connotations of beauty, sex appeal and desirability. By stating so often that he has a "blonde" on his arm, Gill probably feels others will admire, respect, even envy him for attracting such a golden-haired trophy.

I write this because in my view it explains everything about the way Gill evaluates women. In his Sunday Times column this week he started his critique of BBC2's Meet the Romans by saying the presenter, Professor Mary Beard, "really should be kept away from cameras altogether". Why? "Because she's this far from being the subject of a Channel 4 dating documentary." Gill was obviously referring to Channel 4's recent controversial series The Undateables, about people with disabilities and their quest for love: a programme he described in a recent review as a "mocking freak show of grotesques and embarrassments".

After the cheap personal shot, Gill went on to criticise the esteemed classicist's professional analysis of life in the Eternal City, which he has every right to do of course, but I'd rather go with Beard's expert take on things rather than (by his own past admission) an uneducated TV critic's opinion about whether "Rome was really an international, homogeneous funky berg". Er, run that one by me again.

Meet the Romans opened with a very healthy 1.9 million viewers in its Tuesday-night slot. Only a small number have taken to Twitter to criticise the way Mary looks: "Can't she brush her hair?", "Did she try to look so haggard?" and "Shouldn't she be sexing herself up a bit?" were some of the jibes.

My answer is: Why? What's wrong with a 57-year-old woman looking how she wants to look as a 57-year-old woman presenting on TV? Beard obviously doesn't feel she has to conform to the female TV stereotypes we've been force-fed for years. The problem isn't that she has grey hair that looks as if it hasn't been brushed, or that she hasn't sexed herself up; the problem is with some viewers – and this particular TV critic – who equate their idea of what's attractive with ability.

From what Beard has written, it appears she had been stung by the criticism. No matter how clever or strong a person you are, cruel digs about your appearance can eat away at your confidence and self-esteem. Please don't tell me insults come with the territory. I don't buy into the idea that if a woman appears on TV then she should accept derision about her personal appearance when it has nothing to do with her professional ability. Women are targets for these kinds of insults far more than men.

It's been three years since I took a stand against ageism at the BBC. When I won my case in January 2011 the BBC promised that it would do more to represent older women on TV. Recently Mark Thompson, the BBC director general, said my case was a "turning point".

That's because Thompson knows the tide is turning, albeit slowly. A recent poll by the Cultural Diversity Network revealed TV viewers want to watch older women, but not as figures of fun, as some have been portrayed on Strictly Come Dancing, but as role models to whom they can aspire. TV executives seem to be getting the message that viewers don't find wrinkles offensive and that grey hair, is well, just a natural part of getting older – it'll happen to everyone, if they're lucky.

Professor Beard tells a riveting, exciting story of life in Rome; she tells it with the credibility that comes from years of experience in the classics, and as a viewer I like and respect her even more because, in these pioneering days for women in TV, she has the courage to be herself.

As Beard knows better than I, the Roman empire lasted so long because its civilisation kept evolving with the changing times. So put away the prejudice, Adrian, and pull up a seat for Mary's next instalment; you just might learn something.

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