Unfortunately given I've not been an active java engineer in over a decade, I'm getting this from conversations I've had and presentations I've seen from the Java engineers at my workplace and that I've previously worked with. I'm genuinely happy to be corrected though, I've definitely not got a horse in the Java framework race, at any rate.
Perhaps I'm/they're mistaken, but I've got the impression from them that everything is heading towards Micronaut or Quarkus (and perhaps others that people I work with aren't looking at) if you're sticking with Java, and starting something new in SB would be against that direction of travel. Might be worth pointing out that a few of the Java devs seem to be doing more in kotlin as well, so perhaps it might be more to do with that and I've got the wrong end of the stick.