It is dumb and will likely add fuel to the fire and the politicians know this. Canada has like a 68% home ownership rate meaning actually doing something to lower housing prices would be political suicide.
There are two implications of this: 1) NIMBYs need to realize that allowing more housing isn't going to tank prices; if you're worried about prices tanking, you need not be; 2) YIMBYs need to realize that NIMBYs aren't exclusively motivated by greed. When they tell you that they don't want their neighborhood to densify they actually mean it. It's not covering for racism or greed. People genuinely don't want their neighborhoods to change.
There's hope in this. If the state forces upzoning, then people are going to grumble about it. And some of them won't be happy no matter what. But the average homeowner isn't going to be that upset about it once they realize there's money to be made.
Ya, a lot of NIMBYs don't care about housing prices since they aren't thinking about selling anytime soon, they just don't want the traffic and (perhaps) crime that goes along with density.
I get what they mean since I became home owner. I don't want my view to go away, and crime is already a problem (having some random person come into my drive way to check if my car doors are unlocked is quite unnerving when you can see it happen in real time through your cameras). I bought in an already upzoned area, however, so I'm more concerned if my son can get in the local choice school (which is heavily oversubscribed given the density).
Something I've been trying to think through recently is that people clearly have some kind of proximity theory of crime. If there is a murder in the building next door to me, then that's going to make me uncomfortable, whether there is one family living in that building or 10. The obvious urbanist (or generic intellectual) response to this is to say, you know, obviously there will be more crimes in a neighborhood with more families, but you should only care about the per capita numbers, not absolute totals.
And increasingly I just think, yeah, obviously that's right, but that answer isn't good enough. Fear of interpersonal violence is lodged deep in our brains and I just don't think you can talk people out of it. You could make everybody in the city attend a class on crime statistics and quiz them at the end to make sure they understand per capita rates, but when those people get home that night they're still going to be worried about the murder that happened next door. And I don't think it's because they're dumb.
In my experience this is almost 100% the real truth. I haven't met many people that are looking at their house price when they think about changes to the neighborhood. First consideration is usually traffic. Second consideration is character. In neighborhoods where almost everyone owns, they very much don't want to see it become a rental neighborhood.