I don't think it is as much an issue of snowflakery as Keillor is limiting his audience.  He's a talented guy.  I used to listen to his radio show 15 years ago.

But toward the end, he started to really focus on the political stuff - and it just became unfunny.  His articles are the same.  Instead of being a piece of Americana that everyone can relate to, he's constantly needling those who don't agree with his leftist views.