Second - there is no similar freeze on property taxes - or the expected inflation in maintenance costs, insurance, and so on. Again - a tax on property owners by another name.
Third - starting with a rent freeze is an indicator of a property owner unfriendly administration. Any builder would have to calculate this into their expected returns on capital investment.
Which is just fine in my book.
Builders do not have to "calculate" any of this into their "expected returns", because new construction will not be subject to rent freezes or even stabilization. You're selectively ignoring a key part of what the GP said in order to further your incorrect argument, and that's not cool.
As for your first and second points... tough shit for the landlords. That's a cost of doing business. Taxes, even implicit ones like this, change all the time. And a landlord owning a rent-stabilized unit should already know that there are limits on what kind of rent increases they can push through, and that those limits could change at any time, even to zero.
If Mamdani does this, not only is he fucked, but he might take down the national progressive movement with himself.
"Tough shit" is a good Twitter reaction. It's terrible policy. Berlin did that, and it backfired in the most predictable way possible.
New York needs more housing. New York City's public finances simply do not permit a massive public housing construction binge, and Albany can't fund a socialist mayor's public works with upstate tax dollars. That means that housing must be privately developed. New York City, just today, transferred power away from City Council and to Gracie Mansion to help facilitate new housing. That means the impediment is local opposition. The literature shows that opposition gets dampened when folks aren't afraid of gentrification; rent freezes do that.
If Mamdani takes the easy route and "tought shits" the landlords, his housing policy grinds to a halt. Market rents, covering 75% of New York apartments, will spike. The experiment will be over. He doesn't strike me as an idiot, which is why I don't suspect he'll do this.
Like Obama with ACA? He fully thought he'd be a one term president over trying to push it in. Sometimes the best thing for a city is not what's best for reelection. And I very much don't want a candidate who's only minmaxing around what will get him re-elected.
I think we need to have more faith in the people. As gen Z says, "let him cook". We're thinking too Establishment here in a time where we clearly need a different strategy. Establishment had nearly 2 decades to resolve this and it only got worse instead. Why not try a new plan while observing what went wrong before and adjusting?
Or at least be able to scrutinize when the people who want to ruin his 2028 campaign (should he rerun) are the same that tried these same tactics this year. If these tactics were effective, Mamdami wouldn't have gotten in.