I'm not the OP, but generally JVM applications are very resource hungry under small loads, although I will concede this matters less as load increases, and the extreme OOP style of programming that Java encourages, in my opinion, leads to a lot of faults that require more operational babysitting than I'm ok with.
I don't have any empirical evidence, just experience. As such I'm very biased against it.
Java was great at the time it was created. But now, I think there are several better languages that are more suited for today. Like Go as an example. Easy to develop and easy to maintain. You get very good performance for little effort. It is just my personal preference, but I don't care to maintain Java or JVM anymore. FWIW, I was at the very first every Java One conference. Have used it for many years.
It might make sense to revisit your stance given the most recent JEPs that have been introduced. Java 19 introduced virtual threads and structured concurrency, which will arguably make Java + the JVM a great alternative to Go, etc. Especially since it's very backward compatible.
W/ Graal as well, the AOT compilation comes 90% of JIT performance.
I really think the JVM is an exciting eco-system that has a very bright future if it keeps going the way it is. Brian Goetz' "Paving the on-ramp" discusses how to reduce the boilerplate even further. So these things are definitely a priority for the Java/JVM team[0].
It's GPL with the 'classpath exception' so that you're even exempt from the GPL the you link. Seems pretty good licensing? Do you prefer even more permissive than that?
This is no longer a real reason. It's licensed as GPL with a "classpath exception." That's pretty permissive and this article[0] does a pretty good job of explaining some questions you may have.
I don't have any empirical evidence, just experience. As such I'm very biased against it.