Poor Miwa, she knew she was fucked xD.

There's quite a lot of difference in grading amongst all the competitors. Given that there's not very many students at all (only 3 First Graders were enrolled at Tokyo this year), the currently participating students probably form the bulk of students overall (I'd say at least half). Normally it'd be strange to send a mixture of weak and strong participants for a "tournament", but if that's all they've got then that stands to reason. It's officially an exchange event after all.

I can't wait to see Itadori vs Toudou again.