I started this world in 1.16.3 (curently in latest snapshot) I saw things similar to this but those were on old snapshots. My map was working fine then part of it started getting grayed out. I am using data packs but none of them change maps. and it only effects one area. I tried optimizing my world and replacing the blocks neither worked. Edit The same thing happens everywhere in the end so mabye it using the voids textures on top of everthing else