I think there is nothing wrong with doing one's PPL in the USA rather than the UK.
If one spent the £8k+ (£5k is rather optimistic, for most locations and the average ability pilot) at the local UK airfield, this is likely to result in yet another flying school opening up, having yet more "just passing through" ATPL hour builders sitting on the sofas thumbing through the airline ads, so that nobody is actually going to make any money.... In most cases of several fixed-wing schools in a given airfield, one could shut all but one and everybody would be better off.
The thing which would make a real difference would be if one could attract even a tiny little bit more of the very copious money which is splashing around the world outside GA; attract some people with realistic budgets into flying, and then everybody would benefit from extra traffic, extra landing fees, extra tea and chocolate cakes sold, and the holes in the WW2 runways might finally get patched up because anybody with a half decent plane doesn't want to wreck in in a pothole.
I am sorry to say this but there is nothing to be gained supporting the decrepit PPL training industry as it stands. It is a sausage machine, churning out PPLs, of which nearly all chuck in the towel nearly right away. Banging around circuits is of no long term benefit to UK GA. It's not a sustainable business. It is the "bit after that" that needs addressing.