I wonder whether the trait of ignoring science for political or ideological or tribal reasons is inheritable. If it is, the trait will persist just because so many of the anti-vaxxers have already reproduced. However, I question whether the type of stupid that causes some people to prefer rumors and conspiracy theories that reinforce their existing suppositions about the socialist government forcing them to do things they don't want to do is genetic. There is research suggesting that conservatives are more fearful than liberals, https://www.psychologytoday.com/us/blog/mind-in-the-machine/201612/fear-and-anxiety-drive-conservatives-political-attitudes - although this theory has been questioned, https://www.livescience.com/conservatives-not-more-fearful-than-liberals.html - because it appears that conservatives aren't necessarily more fearful than liberals, only that they are afraid of different things. And, the author suggests, it might be that people adopt a political identity first and then fear certain specific things as a result.
Fearfulness in general is probably an inheritable trait. But people who won't get vaccinated don't fear covid, or at least not enough, even though they should (like the caveman fighting off a lion with a stick), but they fear the vaccine. Why? It's not because they are fearful in general, but perhaps it's because their political identity has motivated them to fear the vaccine more than the disease. Arguably this is just plain stupid, but is it low-IQ stupid? Probably not. I'd posit that it's a learned stupidity (and here I define "stupid" not as developmentally disabled in some way, but as willfully ignorant) arising from rigid political identity. It's a social disease, not a genetic one.
But even so, if the 'rona kills off enough of these morons to keep the GOP from winning elections I will be satisfied that their karma has run over their dogma.