The article isn't actually about housing being unaffordable. It says housing is unavailable.

They could build more housing, but no one wants to get caught holding the bag if the boom turns to a bust as the world returns more to normal.

And even if they did choose to build the housing, housing next year doesn't solve the issue of housing today.

That said, where I live we are building plenty of housing but we still can't fill jobs. Why exactly is hard to say, but general consensus is that government unemployment benefits are currently compelling enough that people will trade taking a hit on their income in exchange for not having to work. Can't blame them, I guess.

Seems like a painful readjustment in the coming years as we unwind all the emergency decisions we made last year.