The only long term solution to housing shortages is to build more housing. Gentrification is merely a byproduct of newcomers having nowhere else to go. Short of enacting segregation ordinances there is nothing that can be done to stop newcomers from moving into neighbourhoods in search of cheaper rent other than to build new, denser housing for them.
Did you... read the link? The difference between San Francisco and Vancouver is that Vancouver allowed developers to go up. Vancouver now has more insanely expensive housing than it did but no more cheaper housing. The issue is you can't knock down expensive low houses and build cheap condos; the act of building is in and of itself expensive. You cannot take a business center surrounded by water on three sides, wave a magic wand and make it affordable for new families. All you can do is make existing owners richer.
