Modern Java people are a lot less boilerplaty than old enterprise Java people.

And which modern web framework is least boilerplate? Springboot?

I'm a big fan of Spark.

https://sparkjava.com/

Why Spark over Javalin? I switched to Javalin last year, it seems to have more active development.

Spark is pretty complete. I'm not sure what I'd add to it or change about it that wouldn't be making it bloated.

Seems Javelin is largely comparable, but with a bit more cruft (offering async calls sticks as an unusual decision given the way the language is heading).

What places are doing modern java development?

AWS, Netflix to name a few I know.