You can write concise Java. Just like you can write readable Haskell. It’s just not idiomatic to do so.

System.out.print("I agree.");

It is always dismissed as too verbose, while in go’s case it is never mentioned, when in fact the latter is way more verbose.. People’s bias show.

Code Golf rules allow people to submit an anonymous function instead of a full program, which eliminates a lot of the boilerplate.

They weren't writing enterprise Java or they'd need a dozen factories and a few factory factories and probably a factory factory factory just to be safe.

I don’t know the specifics of the golf problems, but I’m mostly in c#, also notorious for “having too much boilerplate,” and it looks like it’s 3rd by char count.

My guess is that languages with comprehensive standard libraries can do more with less custom code. As you should expect.

I wonder if it's all those variables named with single letter and abbreviations, so annoying to code review

Yes, but it looks like it is already I think more than twice as verbose as Python.

What's interesting to me is how differently C# scored vs Java.