If you grow carrots, you would prefer to keep the overall supply of carrots low so that your carrots will fetch the highest price. But what you are actually doing is increasing the supply of carrots. So incentives and results are two different things and we shouldn't conflate the two.

I assume by "incentives", you mean that they'd manipulate the law to limit other suppliers. I'm sure that happens, but as a landlord you don't have to do that. And being a landlord (who isn't manipulating the law) doesn't make the problem any worse.

Criticism should be directed at the real problems. Those are a mix of law and culture and just inertia.

> what you are actually doing is increasing the supply of carrots.

There's an error in your analogy.

Nobody is growing carrots, they're buying carrots

Incentives push the carrotlords to pass local ordinances. 'Show me the incentive and I'll show you the outcome'

landlords rarely build housing, they usually buy up existing housing and rent it out

and the don't have to do anything illegal to restrict the housing supply - they can lobby, regulate, and vote

I don't know what you mean "rarely", because clearly a lot of housing is built and intended as rental property.

Regardless, the small landlord who buys a single family house and rents it out still puts a new house into the rental market, making it more affordable than it previously was on the purchase market. Along the way a landlord typically makes improvements and pays for maintenance, which improves the supply.

If you don't like laws then complain about the laws. The act of renting a house to someone else is not the problem.