I don't have another legacy console edition world to test on. I would have to create a new one and go around exploring as well as buying a realm subscription to be able to move the world over to W10 and test in the 1.18 beta.
Also, I don't know if this same issue would appear in a world originally created in Bedrock (non-legacy console edition) as I don't have a world as big as my legacy console edition world to test it on.
Been studying for exams since those are coming up but I realized that what you said is right after some testing though I didn't have time to respond right away.
Some random events that occur in the village when in loading at different speeds does seem to be the cause of some of the crashes but I still have to say that the some of the workplace blocks have to something about it or are a different cause of crashes.
Like I said during in the conclusion of some of my tests,
"After doing some more tests with the same seed/village. I have come to the conclusion that the grindstone is the one causing the crashes.
Generated the same seed, broke the cauldrons, closed the world and trying to reopen the same world resulted in a crash.
Tested the other work blocks that villagers use as well.
Doing the same thing but breaking the only grindstone in the village resulted in a success. I was able to reopen the world after breaking it."
The only way I was able to reopen the world was by breaking the grindstone beforehand.
After doing some more tests with the same seed/village. I have come to the conclusion that the grindstone is the one causing the crashes.
Generated the same seed, broke the cauldrons, closed the world and trying to reopen the same world resulted in a crash.
Tested the other work blocks that villagers use as well.
Doing the same thing but breaking the only grindstone in the village resulted in a success. I was able to reopen the world after breaking it.
After taking into consideration that something with villages is the cause of the crashes, I decided to test it.
Doing some quick tests in the seed "Chepo", I can confirm it has something to do with villages. I was able to generate a new world, actually load into the world, close the world and reopen it right at spawn (I didn't move from spawn).
I was able to reopen the world without problems but after going east about 200 blocks to the nearest village, I decided to look for fetching tables before closing and trying to reopen the world, found no fetching tables and it still resulted in a crash.
It's not the fetching table causing the crash but it has to do something with being in/near a village
Can confirm that bug is fixed in the 1.18.0.22 Beta, at least my world (the one attached) doesn't have this issue anymore.