St Mary's and Gonzaga were good last year, return some good players and would be expected to be good next year. Both teams have very good coaches.
BYU returns some good players and have some RM's coming back who may help. Pollsters generally are unaware of returning RM's so don't figure them into their evaluation as they would returning players and incoming players.
RM's are pretty much an unknown commodity. We don't know how good they will be the year they return. They might help a lot, there is that possibility. Or not. We'll see.