You're ignoring that, it's entirely possible allow Y people to live there, without increasing numeric margins on rents. Instead, landlords/investors often look

You're ignoring that, it's entirely possible allow Y people to live there, without increasing numeric margins on rents. Instead, landlords/investors often look to maximize their profit margin as much as demand allows. Which shows, that investors can be a factor to the problem, by either choosing to maximize profits for selfish gain, or keep rents minimized despite excess demand.