Why does so much of politics benefit the person passing the bill at a cost to everyone else. (on net). It's like a market failure, but for the political system.
Unfortunately, when the dynamic system finds a new equilibrium, people are surprised. To this day, people don't seem to understand that rent control suppresses supply leading to higher overall rents.
First is that the costs are hidden and complicated. We need a decent understanding of economics combined with an honest and deep analysis of the consequences of the specific policy to conceptualize why it's deleterious. Very few people will tick both boxes.
Second is that politicians want to be seen to be doing something. Even if leaving the market alone is the best of all options.