Hall and Saunders aren't necessarily gone. If they leave, it is disappointing to me as a BYU fan. That said, USU was able to rebuild a team (including adding a new coach) in less than a year. USU did better than BYU in the tourney (lost to the NCAA runner up–badly). Going to the portal makes sense – you may want to keep options open.
What's crazy is that many players are willing to leave something they were a part of, know and understand for 'greener pastures'.
Note: The kids are being disloyal to the institution. We can toss around "NIL money", coach changes.... all we want, but the truth is that many have no loyalty to the school that they played for. I personally don't understand this, but this new generation of kids appear to be more me-centered than those in the past (gauging from my own kids, their friends and other acquaintances... and college athletes).