Max Fosh has the grace and self-awareness to acknowledge his super-posh, Harrow-educated background. But refreshingly, he doesn't excessively apologise for his privilege and financial resources, which he's fully exploited to enjoy a popinjay's existence of bowling about, doing pranks and reportage on the lives of quintessentially British eccentrics and the upper-class. He makes the likes of Dom Joly and Louis Theroux appear oiks. So why get bogged down in it?

What's perhaps less forgivable is his relentless YouTubing, his insatiable quest for content bordering on a mania, incorporating everything from a London mayoral run to his recent, much reported placing of a Welcome To Luton sign in a field by Gatwick Airport.

A video of his greatest hits in his former persona of Streetsmart, sneaking into the International Security Expo as Rob Banks, occupation' international baddie', or finding the identity of a stock photo model and tracking her down to Australia, offer a pretty good primer as to his five years in his singularly modern vocation.

Aspects of his approach feel intrusive and morally dubious. And there seems little satirical impetus to sticking a microphone in front of fellow aristocrats and waiting for them to babble out-of-touch nonsense. Probably with an element of not wanting to retread old ground, when he recalls meeting nudists at a colony, we don't get to hear from them as he instead focuses on the blink-and-you'll-miss-it exposure of his penis.

Fosh pads out his debut Fringe hour with a recurring parlour game, in which he must sustain a conversation while, unbeknownst to his mark, the first word of every utterance has to start with the next letter of the alphabet in turn.

There's an undeniable appeal in hearing him play this at an exclusive dinner party, eavesdropping on how the other half lives. By the third instalment, though, there are significantly diminishing returns – and one feels a little queasy about him trying it out on his unsuspecting hairdresser or while ordering from a Thai takeaway.

Inspired by a report that the name Gary is dying out, he gets a few solid laughs from raiding the census for more popular but ridiculous monikers. The poor children named after a Swedish supergroup deserve every sympathy. But his chortling at those kids named Jesus seems culturally oblivious to the Hispanic population.

Worse still, when he then hops on a flight to Belfast to meet potentially the last Gary ever to be born in the UK, he gets into a haggling situation with the infant's mother, resulting in him handing over an eye-watering amount of cash for awkward photos with the youngster. Even outside a cost-of-living crisis, it's an exploitative gesture for sub-Dave Gorman quest comedy.

In the same vein, he then recounts how he jumped on a plane to an obscure town in Norway, simply to ascertain whether it inspired the idiosyncratic lyrics to Nelly's 2002 pop-rap hit Hot In Herre. Spoiler alert: It didn't.

The joke is clearly the demented lengths Fosh is prepared to go to for this most trivial prize and his viewers' entertainment. But it doesn't half feel like he's trolling a planet burning up with climate change.

Fosh has considerable front and engaging charm, because how else to explain the closing section of his show, asking audience members to share the notes on their phones with everyone? This segment lives and dies by the personalities of the attention-seeking individuals who comply and the reliability of the technology to respond. 

It reiterates that Fosh is a capable improviser, capable of thinking on his feet.  Even so, it's further padding in a patchily entertaining but truly flawed show.

• Max Fosh: Zocial Butterfly is on at Underbelly Bristo Square at 2.15pm