You’re probably right. I think the form factor is mainly due to sushi being finger food. And Japanese people seem to like bite-sized food anyways. I mean they don’t hand you a knife in the first place so there wouldn’t be any way to cut your food even if you wanted.

I’m not an expert on sushi either. And I wonder if it really has a long tradition of how it’s supposed to be done. I suppose what we deem authentic are relatively new inventions. Like conveyor-belt restaurants aren’t from the 18hundreds. And they certainly didn’t eat raw salmon before refrigerators were commonplace.