re: Jerry Seinfeld is not funny

There are a lot of blazing hot takes here.

The guy got a network sitcom because he killed it on the late night talk shows.
The sitcom, based around his life and his act, is the GOAT and has had a towering influence on comedy. I'm not going to hash out who wrote what - it isn't like he showed up on the set, read his script and went home. I'm sure at the very least he contributed jokes and hashed out ideas with the writers.
After the show went off the air 20 years ago, he's continued to make a mint doing standup.
If you've been making a great living for 30+ years doing standup, you're funny. End of story. It's like all the dopes who go on this site and say Kate Upton ain't fine - you make a great living as a swimsuit model and playing the hot chick in movies, you're fine.