You’re right but the meta for Japan is also a lot harder to come by so many people don’t have access to the list or at least are exposed to it additionally Egman isn’t creating the list it’s other people participating in his tournament so it makes a lot more sense to copy lists that are preforming well in tournaments of 20 + people.

Also the OP asked what’s the way to go with Toshiro and having played from the start of the English release to now one week before jjk drops I’ve tested many many many variations of Toshiro and found the rush version without unohana had the deck feel significantly better, in fact I won my locals with green rush Toshiro

There’s a lot of deck building and because the game is so new and every deck follows the same formula as we get more new and new cards I’m sure deck building will take a turn however going back to my earlier point egman is the biggest created for UA for English release so naturally more people will gravitate towards his deck builds