Ref my bold, Henry and Imogen priced the local kids out of the market, because the local kids parents took the extra money from the Henry and Imogen concerned, thus selling their kids chances of buying houses within the local price range. Don't blame Henry and Imogen for having loads of money, blame the greedy parents for pricing their own children out of the local housing market.
The problem is more complex than that; we don't build enough houses. It's not a local market thing, it's a political thing.
I'm renting a house to a lovely couple of Londoners, copper/nurse, in NW England, they're on 1.5 x 0.9 wages having ditched London weighting and gone part time; they're still a grand a month better off on shorter hours because my rent is waaaay lower.
That's a wages/house prices/planning issue, firmly at Central Government's door.