This seems to be a lag issue. When I set the random tick speed higher, mspt shoots up to 200 on a superflat world. Your world looks like it has more plants which might try to grow, so it would make sense that everything would freeze. For some reason I'm not able to attach the video though.
also this bug looks like the same as MC - 144121
I found the same issue while playing on 20w18a on a multiplayer server, but was unable to recreate it on a singleplayer world.
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Weird. I'm noticing that some specific actions cause extreme player-side lag and sometimes crashes at high random tick speeds. This is not specific to the integer limit though.