I've never had any issues with JWT. There's a group of incompetent developers who like to point to a tool as a scapegoat to distract away from their own failure to use the tool correctly.
I think the irony is that the people who make these blanket statements may be idiots themselves and that's why they think everyone else is an idiot. They can't imagine that other people don't have problems using those tools. It's a skill issue.
Some people here built embarrassingly parallel distributed systems with consistent hashing load balancers. JWT is easy by comparison.
To me, it sounds like a child putting their shoes on the wrong feet, getting blisters and concluding that nobody should wear shoes.