I am not sure if this is of any help, but after trying the newest beta, I experience a repeatable crash when leaving the end (albeit only tested with the /execute in command)

I tried switching off the "rebuild_blockstate_cache_async" option but that does not change anything.
When I loaded the same save (it was crashing on entering the world) with ModernFix 1.6.0 Beta 2, the game worked again.

I do run a heavily modded game, but here is the log. You're doing godly work btw, I literally cannot stand booting up Minecraft without your mod anymore lol.

crash-2023-02-11_17.24.23-client.txt

Do you happen to have the full log when the crash occurs, just in case there's useful information?

EDIT: I think I see the issue. Full log would still be useful to be extra sure.

This is fixed now. The issue was that Better Foliage requires its grass models to be set up before joining the world, which is a perfectly reasonable assumption in a regular game, but not in my egregiously optimized one. 😆

I'm happy to help as much as possible!

Here is the full log
latest.log