If it is economical to build a 30 story condo then you can be assured the area is either a very dense city or an extremely rich suburb. I don't think either areas deserves special protection.

I suppose I would take the above proposal over the status quo if it truly eliminated local control - but otherwise seems like a very long time for a neighborhood to upzone. Its almost never going to be economical to tear down a SFH and build a triplex unless the SFH is in disrepair - which may be after 50 years from initial construction in most cases.