Pat Hanson of gh3* is absolutely right with her comment, here, about why we are seeing more windowless bedrooms being built in Toronto:

In much the same way, some of Toronto’s development policies encourage windowless bedrooms. “I don’t think it’s driven by cost,” says architect Pat Hanson, a founding principal of gh3* and a member of Waterfront Toronto’s Design Review Panel. “It’s driven a lot by building forms. Where you find a lot of these inboard bedrooms is in the mid-rise type.” The requirements to step back mid-rises on an angular plane, she adds, forces the developers to populate their projects with very deep units.

This condition is being driven by building forms and by overall housing affordability. Here is a post that I wrote on this exact topic back in 2017. The numbers are dated. I cited $857 per square foot as the average price of a downtown Toronto condo. But the forces at work remain the same.

And they are not entirely unique to apartments and condominiums. One of the reasons why many condominiums are becoming long and skinny -- and getting designed with windowless bedrooms -- is the same reason that many cities, like Toronto, have long and skinny single-family lots.

You can certainly find wider lots, but it'll cost you.