I don’t know if it is affecting past versions and or other platforms but currently Xbox series X is rendering Minecraft at 4K even if the console’s resolution is set to something else (1080P for me)
In the case of 4K - 1080P it means that the graphics load is 8x higher than it should be.
This is actually ridiculous, how was this completely missed.
Solution:
Add a resolution setting to stop the console from rendering at a resolution higher than it needs to.
or
default to the resolution that is currently selected within Xbox settings.
This is working as intended, see MCPE-177970.