Is it just me or are almost all TV documentaries completely unwatchable these days? I remember when I first started this job I’d review one almost every fortnight. Always there’d be something worth watching: on the horrors of the Pacific or the Eastern Front, say; or castles; or Churchill; or medieval sword techniques. But now it’s all crap like The Hidden World of Georgian Needlecraft or In The Footsteps of Twelve Forgotten South American Civilisations Which All Look The Same or A Brooding, Long-Haired Scottish Geographer Shouts From Inside A Volcano Why Climate Change Is Worse Than Ever.

The presenters have got more annoying too. I mean, I’m not saying some of the old ones weren’t infuriating with their hand-waving and tics and mannerisms and wheezings. But the new ones are just vacuous, unformed squits. They make you yearn for a reverse Logan’s Run world, where everyone under 30 is executed for being so tiresome. A lot of them are women, obviously, chosen mainly for their simpering looks and charming speech impediments and unerring knack for fronting the dullest imaginable subject matter.

No doubt the people responsible for commissioning this drivel think they’re redressing the balance, in much the same way progressive historians do when they demand we empathise with medieval peasants rather than learning about what Edward I did to the Welsh and the Scots. Well, I can’t speak for all oppressed women here, but I think I can for my wife. They’re not going, ‘Oh, good. Finally a documentary with my name on it, about what it was like to be a woman’s maidservant in Elizabethan York.’ They’re going, ‘Who is that irritating little cow? Why is she on the screen putting on that little-girl-lost voice for my husband? And why the hell isn’t this documentary about something actually interesting, like, say, castles, or Churchill or medieval sword techniques?’

Then, of course, there’s the worst thing of all: the journey. All presenters in all documentaries, as we know, have to begin by telling us they’re going on a journey. But as anyone who has ever worked in TV knows, this is a total lie. You know even before your first day’s filming exactly what you’re going to say, what your interviewees are going to say, what your line is going to be. You’re not discovering anything. Even the scenes where you pretend to be meeting someone for the first time are faked.

Something needs to change — and I know exactly what the solution is. We need documentaries to be presented by real enthusiasts, rather than by talking heads who’ve just mugged up on the subject. That way the subject matter will take care of itself because, regardless of what it is, a true enthusiast will make it interesting.

A.N. Wilson showed us the way this week in Return to Betjemanland (BBC4), a shamelessly eccentric, puckish but deeply insightful homage to the poet, architectural evangelist and clown with his ‘infectious toothy grin, the slightly seedy air of a defrocked clergyman, the sharp knowledge and the ready wit’.

It travelled all over the place, from Betjeman’s Cornish grave in St Enodoc’s churchyard to Highgate (where he grew up), the Dragon School (where he developed his buffoonish amiability as a defence mechanism against the tyranny of organised games), via Marlborough to Magdalen, Oxford (Brideshead fantasy), thence to the neo-Mughal splendours of Sezincote (social climbing; great houses), Clevedon Pier (his love of the English seaside offsetting his crashing snobbery), to the remnants of the Euston Arch (which he failed to save for the nation), to the neo-Gothic glories of the Midland Grand Hotel at St Pancras station (where, thank God, he had better luck), to the Wiltshire home he shared with his socially superior wife Penelope (whose father deigned to allow Betjeman to address him by the familiar term ‘Field Marshal’). But at no point did Wilson employ the dreaded ‘J’ word.

Wilson’s approach — the right one, I’m sure — was to flatter the viewer’s intelligence rather than demean it. In this he found the perfect role model: Betjeman himself. Watching excerpts from Betjeman’s 1960s TV documentaries, you were reminded — as with his views on conservation — how oddly ahead of his time, postmodern even, this lovably shambolic reactionary actually was.

There was a scene from his documentary on Weston-super-Mare where Betjeman read from a guidebook, describing how parents could relax in deckchairs while the ‘kiddies’ built their sandcastles. The accompanying footage showed the opposite: kids snoozing in deckchairs; grown-ups making sandcastles. But the joke wasn’t laboured. Another showed Betjeman fluently playing an organ fugue in a church, before telling the viewer that this was ‘a trick of television’: ‘I can’t play a note.’

Where are the Betjemans de nos jours? A.N. Wilson is one, obviously. But we need more English eccentrics unafraid to venture off the beaten track, sod the fake journey and deliver an actual opinion. Modesty forbids me from suggesting who.