Whenever I play the game and use an elytra, boat on ice, or even walk through one of the new caves the world generation gets really laggy and chunks load so slow to the point that it becomes possible to outrun chunks. I tested it in my game without any other mods and the issue persisted. The mods caves appear to be what causes the world generation to lag excessively. It also gets really bad in the oceans and abyssal chasm.

The specs I'm using are:
Intel core i7-8700
32 GB ram
1 TB SSD
NVIDIA GeForce RTX 2070