...restricting density to only a handful of neighbourhoods ... puts them in high demand and drives their prices up.

This sentence should be clarified.

I think it's true but there's more than one factor.

--Low density housing in areas zoned for high density becomes more valuable because of the potential for redevelopment.

--Inadequate supply of constructed high density housing means higher prices for all types of housing.

I generally agree with the column and support higher density across the board. One of the major political hurdles is always 'but my parking!' and 'think of the congestion!'. So I think it's important to prioritize densification in areas where transportation infrastructure has extra capacity or is easily scalable. And where neighborhoods are of not fully walkable yet, on the cusp of walkability. I also think Evo car share is a great service for making car ownership more optional.