Anon, our mesorah is from achronim who say that our level of learning is different in our time. Reading mishnayos doesn’t constitute a mesorah. A mesorah is handed down. Who handed down to anyone today to follow the pashtus of that mishnah?
Rav yisroel salanter writes that everything went down one level; our mishnah is like their mikra, our gemara is like their mishnah, etc..
It’s not for nothing that all the yeshivos follow pretty much the same seder