Politically, Nantucket has come a long way.

1960:
Nixon ~64
Kennedy ~36

2020:
Biden ~72
Trump ~26

It may be that Nantucket Bookworks is the kind of store that sells nothing but Prog/Left books, magazines, etc. I’ve been in a few bookstores like that in metro Atlanta, and finding a title that’s worth reading is somewhere between difficult and impossible.

But even if Biden picked out a left wing book because that’s the only choice he had, he still didn’t have to hold it where everyone would see it as he walked out of the store. It’s obvious that either Dr. Jill (if she was with him) or one of his handlers told him to do that.