Good question. Take the new UK prime minister Keir Starmer. I didn’t vote for him but he’s clearly a serious man. So I think a fair amount of what he says can be respected, however I’m under no illusion that politicians are largely powerless in the bigger broken system.
Discussion
I just read that the guy you propose as a model for trustworthiness labels protesters of murders indiscriminately as right wing extremists and threatens them for protesting, heavily increases mass surveillance, and so on. I doubt that this where the promises that got him elected. Maybe it‘s not the lies that you dislike about Trump but his positions.
Don't underestimate the Brits' ability to willingly vote for some who is very explicitly telling he's going to ride them harder than anything they've experience before...