As time goes by, some conservative ideas become counterproductive to the general functioning of society and thus an increasingly difficult sell politically. Because the essence of conservatism is clinging to an idealized past, this is just a side effect of living in a non-static world. Quite a lot of it is now past its sell-by date, but due to the divisive us-vs-them nature of US politics and the bundling of the rotten with the still palatable, it’s persisted far longer here than it has in most of the western world.
Conservatism won’t go away, sadly. The idealized past will just move to a later period. But at least maybe the moldy leftovers will finally get cleared out of the fridge.