I'm not sure if they refer to how large the language's reach is, but more about how advanced Java is once you stop looking at syntax bloat. The JVM can do stuff that's not easy to do in other environments.

I recall things like updating packages/code on the fly, recompiling fast paths on the fly. Maybe that's not necessary in a borg/kubernetes world where you can just restart things and have your load balancer infra take care, or just run slower code because compute isn't that expensive once you accelerate your CPU-heavy libraries, but cool anyways.

Yes, but the difference here is that Python is talked about all the time, so the online tech world knows that Python is huge.

The comment I was replying to seems to believe Java is a tiny backwater, which is anything but true.

I read it less as "Java is tiny" and more as "Java developers can be peculiarly insular and conservative, by the standards of other communities."

Considering that as recently as 4 years ago I was working on a project where we still had a hard requirement to support running in Java 7, and this kind of thing was not considered unusual, I can't really disagree too strongly with that. Yes, that was still inside of Java 7's extended support period, so there was really nothing unusual or surprising about this, from a Java developer perspective. But that's kind of the point.

It's also not really a bad thing, considering what kinds of things run on Java. Mainframe developers have a similar thing going on, for a similar and similarly good reason.