I think there's a lot of general confusion over that "conservatism" is.
First, it's not "evil" or even "bad". It's a legitimate political philosophy that boils down to minimal possible intervention in society, including but not limited to the economy.
Liberals and moreso progressives, believe that the state can/should if not "engineer" society, exercise its power to shape society and use its machinery to level the playing field. To address inequalities that arise from an insufficiently regulated free market system.
If you buy into the notion that these are the primary, functional differences between liberalism and conservativism, you cannot escape the conclusion that a part of the reason for the rise of the hard right is the "gains" made by the liberals towards their "better society" goals.
These liberal "gains" include state intervention in free speech, reduction of personal property rights and freedoms, so-called political correctness, identity politics, redistribution of wealth via taxation and a slew of other things cheered by the left and reviled by the right.
Every time there is a gain that the left cheers, the right moves a little further right and gets a little more angry.
Every time the right gains or undoes something the left feels a deep existential angst and loss of optimism.