Written a lot of Java, Python, and Go in my career... every single time I see someone take a hardline stance against Java it's always because they had one particular bad experience with it 15-20 years ago and couldn't bend it to their will like Python or Lisp. Or they fought Maven, or some other ancillary tool. Or they rail on the generics and yet the use-cases they come up with for true reified generics are generally niche.

Java's got problems. The biggest one is the framework laden ecosystem and that some of the frameworks are all or nothing. But the language and runtime are rock solid. I don't get the hate.