You should be careful with "the same people" arguments. They're almost always fallacious.
> Ramp up the taxes and the incentive they have to fight the denser housing will dissolve.
Ramp up the taxes and the incentive they have to fight the taxes will increase proportionally. Why wouldn't they capture that just like they captured zoning?
The real problem behind zoning is jurisdictional. As long as it is done on a city-by-city level, cities only have to be held accountable to the residents, not the people that they displace across their arbitrary borders. A regional jurisdiction would force zoning decisions to take into account everyone in the region, containing all the suburban residents with terrible commutes that are made worse by NIMBY protections.
Of course. The rich will fight tooth and nail to keep their entitlements. Always have done, always will.
>Why wouldn't they capture that just like they captured zoning?
They would. However, zoning is an easier process to derail because it's more localized and easier to come up with plausible sounding bullshit reasons why something shouldn't happen. In politics you shouldn't attack the shield, you should go for the jugular.
Also you could "fix zoning" and it would still be palliative at best if valuable land is ultimately still being hoarded.
Property developer profits would be higher though.