Revolting (Tuesdays) is the BBC2 comedy series that spawned the now-infamous sketch ‘Real Housewives of Isis’. It has been watched on the BBC’s Facebook page nearly 30 million times and rightly so because it is fearless, funny and near the knuckle.

A pastiche of reality TV shows set in places like Beverly Hills, the sketch depicts three young British jihadi brides brightly discussing their domestic lives in some Raqqa-like hellhole. ‘Ali bought me a new chain,’ boasts one, ‘which is eight feet long. So I can almost get outside, which is great.’ Cue shot of black-hijabed housewife lurching towards the doorway of her bombed-out home, dragging the cooker to which she has been leashed.

In another scene, one housewife proudly does a twirl as she shows off her new style acquisition: a fetching suicide vest. But, oh the embarrassment: in walks another friend wearing an identical outfit. ‘Oh. My. God. It was so cringe. Hashtag Matchy Matchy,’ comments one of them in a piece to camera.

The humour isn’t subtle: ‘This is my sixth marriage. Been married five times,’ one confides to the camera. Then there’s an explosion in the background. ‘Six times,’ she corrects herself, with a wry, what-can-you-do? smile. But it packs a punch because it’s so dark and courageous (barely a handful of TV dramas will dare touch the subject of Islamist terrorism, let alone comedies: this must be about the first to do so since Four Lions) and well observed.

Sure, if these were real jihadi brides, they wouldn’t be in hijabs but in garb so unrevealing it would make even a burka look like a bikini. But the characters and the acting and the situation ring true: the forced domestic normality in the face of grotesque adversity (‘It’s only three days to the beheading and I’ve got no idea what I’m going to wear’), the Brummie and northern accents, the teen-ie giggling and hashtags and selfies. This is comedy doing its job: acting as a release valve for the pressure of the unbearable, testing the boundaries of taste, laughing in the face of evil.

What’s both surprising and disappointing, though, is that the satire in the surrounding sketches should be so lamentably poor. It’s as if two teams were involved in making the show: Team Bold, responsible for ‘Housewives of Isis’ and this week’s unforgiving take on Pakistani child brides; and Team Utter Predictable BBC Crap, which handled most of the rest.

But I’d say it’s the latter, unfortunately, that is the show’s default position. I blame the show’s creators Heydon Prowse and Jolyon Rubinstein, who have exactly the politics you’d expect of two comedy performers who first met at a Hampstead public school: glib, impeccably right-on, metropolitan-chattering class, slightly guilt-tinged insta-lefty.

The Guardian’s critic Sam Wollaston got it pretty right when he branded their breakthrough (BBC, natch) series The Revolution Will Be Televised as ‘Sacha Baron Cohen with a bit more substance …or Mark Steel with a few more laughs’. Yes, they do indeed give you that same uncomfortable, even tainted, feeling of Borat/Ali G cringe as they head off in character in order to expose not always deserving members of the public to ridicule; and, yes, there is, too, something of that leaden earnestness that you find in Steel’s achingly tedious activist comedy. But I think I might dispute the ‘few more laughs’ bit.

Take Rubinstein’s intense investigative reporter Dale Maily who — you’ll never have guessed this — parodies the (as he clearly sees it) aggressively right-wing, tub-thumping, borderline racist politics of the Daily Mail. In this week’s Revolting, Dale Maily visited Broadcasting House to jab his intrusive mic into the faces of various apparently unsuspecting BBC employees — a black guy in African garb, an Indian girl in the lift, Vanessa Feltz in the ground-floor café — to accuse them of representing a hotbed of terrorism and overpaid excess, before glowering with his trademark scowl at the camera to indicate his trademark outrage, scepticism and disgust.

Well, yes, perhaps Daily Mail readers do think that the BBC is a nest of pinkoes. But are we really sure that, of all the myriad aspects of the BBC, this is the one most worthy of satire? Isn’t it a bit like going really hard on the Nazis for being totally obsessed with fancy uniforms: perfectly true, but maybe ducking the key points slightly?

In the name of balance — BBC-style ‘balance’, that would be — our intrepid duo of BBC-endorsed satirists set out to take the mick out of the left too, by assuming the guise of two Labour activists, one Blairite, one Corbynista, to troll an anti-nuke demo in Parliament Square. Except the trolling is so low-grade as to be worthless: sometimes their victims have their faces pixellated (because they wouldn’t sign release forms?); sometimes the exchanges are just not clever, witty or damning enough to justify the effort that went into filming them.

A bit like the puppets on Spitting Image, Prowse and Rubinstein look great on screen but their content is lousy. They need a scriptwriter. They need to get outside the BBC bubble. The ego- and career-boosting controversy they got from Isis housewives isn’t going to help.