The frozen thing was in reference to salmon just to illustrate there is an individual process/know-how for each type of fish. I’m certain your tuna is amazing. But proper sushi chefs prepare every fish in a certain way to bring out a specific kind of flavor/texture so it’d be a different thing altogether. Korean fishermen who know what they’re doing also eat raw off their catch out at sea for certain fish the same way you describe. What I’m suggesting here is that most sushi places that didn’t go through this training don’t bring out the texture/flavor/fish/rice ratio and to a certain extent safety properly.
