Emphasis on 'to a certain extent' :)
Educational outcomes need to be improved yesterday, no disagreement on that.
There's some displacement, yes. However anyone who isn't in privately rented accommodation would be choosing to leave, perhaps even with some decent money from selling their house.
Many people stay, if you'd like proof, take a walk down to hackney.
A "gentrified" community will involve higher incomes for those non-tradable services that have to be provided locally and can't simply be outsourced to somewhere else. So it's both.
(This is in addition to the high productivity that's driving the gentrification in the first place, which will often result in increased opportunity in that very sector - but that's not always very relevant, especially in the short term.)
are you saying that gentrification of Hackney did not simply entail wealthier people moving in and displacing the local population, but rather soaring incomes for the people who lived there?