Probably worth mentioning that thread is a year old and some of those issues may have been addressed by now.

The latest reference (from 9 months ago, so not much more recent) I could find for occlusion culling[0] says it and LOD are planned for the Vulkan branch, so those are still issues.

[0]https://old.reddit.com/r/godot/comments/emachb/how_long_unti...