Thank you for your thoughts and your kind concern, Tango Victor.
You're free to doubt me, but I have done the sums and I have spent many periods of time in the USA, so I think I have a good understanding of the costs. And unless I've made a gross error on my spreadsheet, the £60/hour saving of flight training in the US rapidly adds up to pay for the journey there, the accommodation, and additional living costs you mention.
But as I said before, saving money isn't my primary aim here - financially, I aim to break even compared to achieving the same hours in the UK. The point is that it enables me to complete roughly half my basic training in a concentrated and efficient way, and brings achievement of my PPL several months closer.
I'm sorry to hear of your acquaintance's bad experience in Florida. Searching these forums, I've found glowing endorsements of a number of US FTOs doing CAA courses and relatively few complaints, from which I conclude that the bad experience was a misfortune no more common than sub-standard service from a UK FTO.
If the unfortunate state of global politics dissuades you from training in or visiting the US, I can understand that. But for me, the moderate inconvenience of the bureaucratic hoops appears not to outweigh the benefits of US flight training, and perceived asymmetry of inter-governmental relationships is irrelevant.