Visiting spawn chunks and the surrounding chunks around it causes massive lag spikes that freeze time and make playing impossible. Blocks will not update, day/night will not progress, player movement rubber bands. Problems persist even with the lowest graphics settings and optimization mods do not fix the problem either. This needs to be addressed ASAP as the game is not playable in this state. Problem began in 1.20 and persists in 1.20.1. It may only affect old worlds that have been updated. It is possible that it is caused by villages, I haven't done enough testing to see if that is the case.