The BBC is no longer the much loved, if rather wayward, Auntie of old. Auntie has changed into a monstrously obese, greedy, demanding, confused and destructive old bat. She has traces of her old charm and brilliance; on her good days she’s wonderful. There’s nobody like her.

However, if she is to avoid being sent off to oblivion in a distant old folk’s home, she needs a severe talking-to. Someone must tell her she simply can’t go on like this, and fortunately she has just the favourite nephew to do it - Sir David Attenborough.

In his gentle, lucid way Attenborough explained last week what public service broadcasting is, or ought to be. He gave the first in a series of speeches arranged - admittedly - by the trustees of the BBC, in advance of its submission to the regulator Ofcom’s public service broadcasting review in June. What he said, with all due respect to this national treasure, was obvious. Public service broadcasting is about serving the public and there were moments, he said tactfully, when he wondered whether that was what the BBC did.

Public service broadcasting means an effective network that produces a range of well-made programmes, particularly in the less popular genres, which are financed according to their intrinsic needs and not the size of the audience. Who can disagree? Chasing ratings is not what Auntie should be doing. Yet the BBC TV schedules are stuffed with cheap, populist rubbish, which can hardly be said to be needed since the commercial producers make them with even greater enthusiasm and vulgarity. “Intoxicated”, as Attenborough put it, with the popularity of such genres, BBC1 and BBC2 have allowed them to run rampant like some nasty kind of pondlife and crowd out other programmes.

“Do we really require so many gardening programmes, makeover programmes or celebrity chefs? Is it not a scandal . . . that there seems to be no place for a continuing series of programmes about science or serious music?” . . . It was “very, very sad” that the science show Tomorrow’s World no longer had a place in the schedule. “If you want an informed society there has to be a basic understanding of science.”

My delight that Attenborough said it is equalled only by my fury that the BBC has been wilfully deaf to it for decades, and my rage that it will almost certainly ignore it now. Is it likely that Attenborough, for all his influence, will be able to break Auntie’s delinquent mindset now, if he and countless others have failed so far?

When I first worked in BBC TV, in the late 1970s, in different departments, I went to countless meetings where middle and senior management discussed with programme-makers the primary importance of audience figures, the absolute necessity (in order to survive) of competing across the board with independent television and therefore the inescapable duty of dumbing down and becoming more “accessible”, meaning ever less “elitist”.

I was amazed. I had naively assumed that the point of the BBC was that the taxpayers’ money had set us free from all that. Occasionally I suggested that the BBC should be doing the opposite of dumbing down. Once or twice I muttered that there was surely no need for the BBC to aim at being on air round the clock: that would force up costs and bring down standards. I was made to feel rather silly.

So it has proved. And it did not protect the BBC either - rather the reverse. Auntie now shrieks for ever huger sums from the licence fee, to general resentment, while at the same time axeing or sidelining some of what’s best.

Auntie is wilfully producing lowbrow drivel and comfort viewing, at the taxpayers’ expense, when the open market can supply it in unlimited quantities. Broadcasting such stuff drives the BBC’s rating, but “ratings” are no way to determine the value of public service broadcasting. In the world of free market competition, the numbers of viewers and the numbers of profits are the right way of rating oneself. It is just the opposite in the protected world of public service broadcasting; that is precisely why it is protected at public expense - to preserve and promote good programmes, good ideas and new possibilities that might not survive in the open market.

People are increasingly sceptical about public service broadcasting. In my view that’s partly because the BBC has dropped its standards. Despite all that, I remain a supporter of Auntie, if only she would behave herself, remember who she is and lose a lot of unhealthy fat. At a time when the media are so cynical and exploitative of their audiences, it is wonderful to have one organisation that need not be driven by greed and ignorance but by the best of our shared standards and interests. It could even be the salvation of our failing education system.

The BBC doesn’t need to compete for audiences with commercial media and would be much better if it didn’t. It is also true that the BBC ought not to compete. It is unfair. Not only has it undermined itself in doing so, it is gravely undermining those who aren’t protected by the state - those commercial producers whose livelihood is sport, reality shows, lifestyle, showbiz gossip, imported third-rate sitcom, and so on, which the BBC has no need to do. Arguably, this applies to the BBC’s website, which is subsidised at the expense of commercial newspapers. It cannot be right that the BBC uses public money to grab at and distort a market that has little or nothing to do with public service; Auntie is being a bitch in the manger. Independent media executives have been vociferous about this for some time, some even demanding a share of the subsidy.

Now Ofcom has come up with the perfectly absurd idea of forcing the BBC to “top slice” millions of pounds from its £3 billion licence fee income and hand them over to commercial companies to support their public service programming. It defies belief. What Auntie should do is stick to public service, which she used to be good at until she got all hot and muddled about markets. She should stop grabbing at what other people do and come to her senses. Otherwise the old dear’s days will be numbered.

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