This is weird behavior. Usually, when you pause the game, you need less FPS/GPU load, but actually, the FPS/GPU load is increased.
This is not a duplicate. 1.16.5 has the same issue.
GPU load increases, FPS increases. But I think the GPU load shouldn't affect by the player's moving state or the game's pausing state.
Tested on 1.19.2. Everything seems good. Now the GPU load is always near 100%
I hope that in the future the game can limit the FPS when in the background to reduce GPU usage
This issue can be closed