I disagree, I think the techniques are not the issue, but the political-economic will to actually do it. It doesn’t matter if we discover a way to build a zero-footprint efficiently-dense accessible and affordable housing out of entirely reclaimed materials- zoning boards, HOAs, city officials, and all other sorts of shit-eating bureaucrats and busybodies are going to chain themselves to historic parking lots to prevent progress.
To that note, repurposing a parking garage into shelter makes it easy for them to evict the housed and turn it back into a parking garage as per its original design- even potentially arguing that its original design as parking makes it unsafe for human habitation (and they very well could be right- cars and car infrastructure can be very toxic).
Tearing down car infrastructure isn’t just symbolically obliterating car infrastructure, it has very real impacts in making it hard for the pendulum to swing back to building housing for cars and not people.