I'd question how much of those areas are truly gentrified. Islington, Notting Hill, Battersea, Hoxton, Shoreditch, Stoke Newington, Clapham etc are all areas with oases of nice middle-classness surrounded by much larger areas that are, for want of a better word, slums.
I'm afraid that if your analysis of London property is based on Notting Hill and Islington not being gentrified, then you're far too radical a mind for me
For someone who is sufficiently well off that £800k is a proportionate amount of their overall wealth to commit to a house that may not matter. They can probably afford private schooling and don't need to use public transport.
That's the point: there are plenty of people with the money or the ability to borrow the money. 1 in 10 of children in London (not just owner-occupier children, all children) is privately educated. Camberwell is actually well placed for private schools: bussable south to the Dulwich schools and north to the City or Westminster schools
I would argue that wealthy people living in an particular area doesn't necessarily mean it's gentrified, it may just mean they live in gilded fortresses. Unfortunately I don't think I'll ever be that rich so I'm looking for an area I can live in, rather than shut out.
Maybe this is why you have your unique definition of gentrified. It doesn't mean homogenised wealth. That's the suburbs. Believe it or not there isn't a state of war between rich and poor. Sure for the most part different groups have their own pubs or restaurants or churches or even shops, but many many people (including some well-off ones) actually enjoy that diversity and consider it a good reason to live in central London rather than some rich ghetto in zone 5.
My mum gets very excited about the Bellenden Road conservation area, even though there was a bus burning on the edge of it last summer!
One burning bus doth not a riot make
No argument there! Prices have been remarkable 'sticky', even allowing for near-zero interest rates etc. I suspect that there are quite a few people who want to buy in London for some time and have been saving up big deposits while waiting for prices to fall to a level that doesn't require an amount of personal debt that looks unsustainable (looking at history in the medium-term). Personally I've given up and am now looking further afield.
Genuinely no offence meant, but I think you might well be happier further afield
Indeed. But not just yet.
...and that's what makes a market