Sure, but I think that there are two things that differ between Moyes and other managers:Agreed. If Klopp, Pep, or Jose came in after SAF, you'd expect them to bring in their own staff. The problem was hiring Moyes in the first place. The fact so many are saying he needed SAF's assistants to stay on just illustrates that even more.
1) Moyes was labelled as a manger who will continue United's way (whatever it means), and it was all about continuity. How better to continue than by keeping the staff which was here for a long time.
2) Pep/Klopp/Jose's assistants have won plenty of trophies and have been coaches on the highest level. Moyes staff had won nothing.
Moyes should have kept the staff of Fergie, but in the end of the day, I very much doubt that it would have changed much. He was out of his depth, simple as that, and he apparently doesn't listen much to other people, so likely it would have been even worse (if it was possible) with a staff mutiny against him.