I thought this was explained nearly 40 years ago

There are some conservatives that are funny...but they don't make a lot of political jokes, because making jokes about the poor, minorities, and other underdogs is not so much funny as it is mean and pathological. There, you need no doctoral thesis.

Conservative comic Evan Sayet blames media gatekeepers for keeping right-of-center comics out of traditional media outlets.

Oh yes, it's the so-called liberal medias fault...that you are not funny.

Again, this was explained some time ago, in a far away exotic land: