I did not watch this roast, for the exact reasons and seemingly mirrored jokes(?) you mention from the last few I saw.

You are totally correct. These are not the roasts of yesteryear, nor are they the ribald, x-rated humor of Redd Foxx, Moms Mabely or Buddy Hackett.

Amidst their foul mouthery, there WAS humor. There is no humor here and now. I'm no prude, and have an amazing tolerance if the material is funny. But this stuff is not.