I really don't understand this argument. I didn't want Moyes to be our manager because i never believed (and i still don't) we would be able to challenge for the EPL and the CL under him. The times have changed and we have to compete, both domestically and in Europe, against clubs that are willing to spend more money than us in each and every transfer period.
The key to compete with these sugar daddy clubs is having a good manager. I don't know if Moyes will achieve in the next couple of seasons what he hasn't in his whole managerial career till now. The fact is that, right now, he is a midtable manager and he has turned us into a midtable club this season.
Last summer we had the chance to appoint one of the best managers in the world. So, after the season we had, Moyes' best defense line is that he is loyal and he is here to stay for a many years, while Mourinho would leave after 3 years of success? If if that's the only thing we're looking for in a manager, then call Moyes and give him a 15 year contract. The Glazers should sign it with their blood! What else are we going to hear?
I would take 3 years of success with Mourinho over 6 years with Moyes out in the desert any day. You want to to take the risk of signing a manager who's willing to stay here for a long time? Get Klopp, Simeone, Van Gaal or anyone else who has actually won something, who has competed at the highest level and is known for playing modern football and give him the keys to the club. It's really that simple.