Here in the US it's because rents for the last few decades are being driven by subsidized housing, that along with the gentrification (or in other terms the systemic plan to displace minorities and the poor out of the inner city so the yuppies and millennials can play Friends) is what's driving a high rent market. Since the development of Section 8 housing each year the rents go higher, landlords see other landlords getting high rates of rents so they started charging those rents. These government run apartment complexes are usually ran by investment companies with a high rate of return for investors because the rents are guaranteed money coming from the government. I think the tide towards the government wanting to build more of them in suburban area's is that many of them need a low wage labor force and is not so much about diversity or the climate change agenda's of building more energy sustainable housing. I think what we are seeing here is a model slightly better than that which China uses where people actually live on the grounds of the companies stacked fifteen high in bunk beds working sixteen hours a day so they can pay the company rent and utility cost. These subsided housing complexes have minimal room allowance for an outrageous price but it sure does beat paying people directly a universal basic income to cover an inability of millionaires/billionaires to pay a sustainable living wage, this way the money flows into the pockets of the rich and the poor can't waste away the money if the government sends it directly to them. This, in my opinion, is also why you see them talking about the need for light rail systems that will enable commoners to get back and forth from work which right now is the biggest hurdle to the plan. They want to claim this is all about diversity and climate change but in actuality it's a masterplan carefully crafted to disperse a low income labor wherever a demand calls for it while simultaneously creating a system whereas it encourages investors to build low income housing.