> The idea that SF should be redesigned and reconstructed until such time as supply is so plentiful as to bring down prices an order of magnitude, to me that's the offensive bit.

Not sure where you get the idea that it should be redesigned, but I do think that incremental [1] upzoning in places where demand exceeds supply of housing (in SF and beyond) makes a great deal of sense.

[1] https://www.strongtowns.org/journal/2015/12/16/incremental-d...