I’ve recently seen a video of one of Tom Scott’s mates who went and did drag. It was pretty interesting to learn about it, but one of the things I had to think of when reading your comment was that in the video it was made very clear that US drag and UK drag are very different. In the UK it stems from performative art, in the US it was different. I can’t recall what it was exactly, but I think that explains the sexual focus in the US compared to the UK

Here’s the video: https://www.youtube.com/watch?v=nUf8-P3d5mk