Hello,
I've been playing on an world and sudently chunks stopped loading. The game freezzed, and the chunks were loading like 1 per minute. Restarting or optimilizing the world didn't help. So I runned a server with this world, and got the logs below. Playing on vanilla minecraft and vanilla server 1.16.5. Also, when I go into overworld, the chunks load normally. End also works fine. Only the nether is bugged. VERY annyoing becouse I wanna play with friends. It also seems like the render bug only affects this world.