Because they aren’t “conservatives”, that’s just a label they slap onto themselves and their changes are more radical than those they label “liberals”. What they really are is what you’ve said, voters more susceptible to believing lies, the psychotypes that have been identified through social network big data profiling that are particularly susceptible or within a network susceptible to manipulation. That’s also why a lot of these social network are pretty shameless about how they want to stimulate fake AI users. It is the cattle-lification of social network for those with the wealth and the power to do it, to such an extent that you terms like 1984’s “doublethink” apply quite aptly well beyond the theoretical.