The easy answer to the title question is that Scott Adams gained enough wealth that he lost touch. That seems to be a common experience of commercially successful artists. The author never explores this explanation.
That's not a good explanation to me. Think of Hollywood: dominated by wealthy and out of touch artists. With very few exceptions, they all publicly express politically correct and safe ideas that ensures they keep making money comfortably. That's the total opposite of the direction Scott Adams has been going.
The reason why Hollywood talks a lot about diversity, inclusion, feminism, gay rights, human rights, etc, is not because everyone in Hollywood independently decided those things were good. Far from it: this is the same town that circled the wagons around Roman Polanski, after all. And their institutions were built on the backs of bright-eyed female actors being drugged up and sexually harassed. They are genetically tainted[0] against social justice.
What happened to make Hollywood care about this is very simple: the people who fought for the rights of the oppressed figured out how to weaponize social ostracism and public shame as a political tool. And this is not the first time this has happened, of course. The 50s saw Congress blatantly purge Hollywood of leftists through ostracism; and there's a whole right-wing strain of cancel culture[1] that rarely gets mentioned. Even deep-rooted tendencies have to bend in the face of external pressure.
Ostracism isn't unique to rich people, of course. It can happen within any social structure[2]. The difference is where people get cancelled. If you've been fired from your job for going on right-wing rants all the time, you go and get another job. If you've been given the national spotlight by becoming Twitter's Villain of the Day, that reputation will stick to you forever. And that latter scenario is way more likely to occur to people who are already well-connected, well-known, and have something to lose.
In other words, famous people tend to seem detached from the rest of us because they are looking down at us from space. In the same way that any one of us might be a little detached from, say, someone growing up in the 1950s.
[0] As in, I am deliberately tarring Hollywood with the genetic fallacy. #NotAllMovieMoguls
[1] Remember when they cancelled the Dixie Chicks for hating the Iraq War?
[2] Which, inevitably, will form into a nested hierarchy of cliques.