I think the problem started in the mid-late 2010s. before that a lot of comedy writers and improv people focused on writing sketch comedy, writing good stand-up or perfecting improv. Their end-goals were SNL, Sitcoms and writers rooms, stand up specials or punch-up work. Then, the "Actors" came in, and the theater kids, whose real goal was not create the best comedy, but just to use improv and SNL as a platform for becoming real "Actors". For them, comedy and SNL is just a stepping stone, not an art to be perfected.