On the other hand, a widespread capability of WfH, which wouldn't be possible without tech, or at least not in contemporary volume, is likely putting a downward pressure on housing in attractive areas.

If a well-earning programmer settles somewhere in a rural place, it means a) more money spent in a small community, b) one fewer affluent person seeking housing in an urban hotspot.

I would guess that the aggregated effect worldwide is an order of magnitude higher than whatever passes in Portland and SF.