As I thought, the article is a lot of faff and speculation, based on very little hard fact. It actually revolves around the 'free speech vs hate speech' argument. A debate which has been rumbling on for a while in the UK. Muslim advocacy groups have been calling for certain things to be made hate speech, which would be tantamount to introducing blasphemy laws by the back door. Several prominent ex-Muslims and critics of Islam understandably take issue with this. In addition, we've seen hate speech laws weaponised against multiple women over the years, for the crime of saying men can't be women. This has had a misogynistic and speech-chilling effect, and has understandably led many people to have concerns about what, exactly, is being classified as hate speech these days.
It's a thorny issue, and I'm certain Tatchell is bringing it up in relation to the recent Supreme Court ruling. He is careful to refer to "homophobic hate speech", but I think the many gay and lesbian people who have butted heads with him over the years will see through that. His real agenda is pretty obviously protecting the feelings of trans people. He's soooo careful not to bring it them up in the article, but it just makes it all the more obvious.
On the topic of tariffs: Trump imposed them on everyone. Even his allies, like Israel. This isn't some grand plan to subdue the UK because he desperately wants access to this market. He's doing it to everyone. And he has plenty of trades partners to choose from. I doubt the UK is that high up on the American agenda, to be honest.
Vance is a free speech absolutist, as most Americans are. But Trump's current government talk a lot and change their minds on almost as much. I'll wait to see what actually happens with any trade deal. Rumours from unnamed "sources" don't hold much weight with me. My honest take is that this is all hot air, and Peter Tatchell is trying to scaremonger in service of his own agenda.