Anyway, gentrification. Although it's nice to pontificate on the whys and wherefores of whether gentrification or increasing affluence of an area, the truth is that none of us have any control over it whatsoever. London is littered with luxury housing estates that ended up being slums and cheap tenements that ended up being luxury flats.
Naturally, people congregate where there are other people in similar circumstances or with similar backgrounds to themselves whether they are ghettos or luxury villas and this in turn has a self-reinforcing effect. For example, if there are a number of Chinese people in one place, it makes sense to open a Chinese supermarket. This in turn draws more Chinese people until demand for housing goes up faster than supply and rents and house prices eventually keep out poorer Chinese people who then are forced to either live on the outskirts of the area thus negating the benefit of living near the supermarket or other amenities that have sprung up in the meantime. Of course, the rise in prices attracts investment and speculation which in turn makes the area attractive to other people until eventually, a new richer group moves in forcing the Chinese to either move out to the outskirts (thus driving up prices there) or set up home miles away. Of course, the gentrification undermines the attraction of the area in the first place, the Chinese Supermarket goes bust and is replaced by a Waitrose and the gentrification reaches its natural ceiling and the whole thing starts again somewhere new.
I haven't really thought this through, but unless we introduce laws preventing rent and house price increases, it seems gentrification is an inevitable consequence of the mobility of capital.
Forest Hill may indeed be gentrifying, but there ain't a lot we can do to either support or prevent it.