I have no questions or anything like that, but thought this was interesting enough to share here and maybe inspiring. Also since the Cities: Skylines 2 performance problems were discussed a bit in another thread… this fellow seems to know why you can run Crysis but not Cities 2…
That was really interesting! Thank you!
Obviously JME does frustrum culling, does anyone know if it does any form of occlusion culling?
A good question. I don’t know.
But happened to watch a video on what is new in Unity 6 (to be released in 2024). Looks like Unity, prior to this, had a occlusion culling similar to what was explained in the OP video. That one needed to manually bake it in the editor. Unity 6 however has automatic occlusion culling done on GPU! That is something to research and implement to jME too 
I saw a gpu occlusion culling demo by nvidia not too long ago. Maybe worth checking out?