Obviously this idea is dumb, but I'm concerned that it's the only realistic way to expand housing in the bay. The bay is currently short a solid million housing units, as far as I can tell there currently is no solution to this problem. All the areas that have already been developed are politically captured by NIMBYs that refuse to allow housing to densify. A giant conglomerate coming in and just throwing up a ton of housing on currently uninhabited land is imo the only solution other than the state or feds just unilaterally ending SFH zoning which I don't see happening.
Would not SB9 (or some recent law whose name I forget) allow lot more housing to be built? Not tomorrow but surely over the next 10 years. And then there are so many condos coming up near BART etc. We may be a million short, but I think dynamics start changing with every 100K, so as long as enough people start moving towards ADUs, and 4 houses in place of 1, it will start moving the needle.
A lot of time it is a question of cost, and a lot of times it is a question of cheap property taxes. Remove those blockers and it may make things move faster.
In India, a lot of "builders", come in and offer to rebuild your house for free as long as they can get 1 floor for themselves. Same can happen here - rebuild a house to break it in 4 units, and the builder keeps one for themselves (to sell). Maybe with the higher cost, they keep half to see - I do not know, but you just need a few dozen people to show this initiative before it becomes a bandwagon.
On the property tax, we already have some incentives for people to move elsewhere and keep the low tax rate. I wish we could also apply a floor to the property taxes - yes you have had 2% max raise this past 30 years, but if you are in the bottom 10% (decile?), sorry but we will raise 5% going forward until you are not in the bottom 10%. Slow and steady, but see the incentives change over a decade or 2.