Most people really don't prefer a rural setting. People go to these "high GDP" places because there is a greater abundance of opportunities there. Relationships, friends, career, networks, etc. Even if you can work rurally due to remote work, you miss out on a lot by not being where other people are.
Of my close friends from uni days, only one lives in london, and that’s by choice (her job was moved from london to somewhere in Surrey well before covid so she was “reverse commuting” several times a week.
The others live in a seaside town in devon, a Wiltshire village, a Shropshire village, and one lives in a small Derbyshire town.
London's population is still growing, and faster than the UK population. People want to be in cities, not just because there are more jobs there. Definitely dependent on demographics though.
Worth noting that London is one of the most ethnically diverse cities in the world. Over a third of people there were not born in the UK. There could be many reasons for this including high salary jobs, but other reasons like parking assets in a relatively stable democracy, emigrating to a culture similar to their own, I'm sure the list could go on.
And perhaps because those people are capable/willing to emigrate are possibly more likely to contribute to the economy, there is a net gain for the whole country. Clearly there are reasons why London itself is highly diverse with its international arrivals.
Beyond an economic gain/crutch, does it really benefit members of the same country hundreds of miles away, other than being subsidised by the spoils?
The preferred rural setting for wealthier people in Britain is the villages surrounding London, especially the ones with a decent rail connection to London for trips to the theatre, concerts and so on.
Most people prefer having a house and a garage/shed/garden. They go rural not because they like that but because that's only achievable way to get that. I'd absolutely love be in exact same spot in city but own a house instead of renting an apartment
1) Why did you think that?
2) Why do you assume that people are only in "high GDP areas" for work?
Personally I moved from rural New Zealand to London and I work 100% remotely.