While messing around in the new snapshots (20w45a - 20w46a) I noticed that when using commands, namely the gamerule commands, entities, blockstates, and commands would just stop working, and occasionally I would also get really laggy.
I don't know if this is just me or not, because my computer is no stranger to being super laggy or to stop responding, however this has never happened to me on other versions of the game on this computer before.