Potential is one thing but it's a hell of a gamble to put a manager with no kind of record at the very highest level of football in one of the biggest management jobs in football.
So all top managers who win stuff start at a top club, and have all won something previously?
What competitions apart from the league and FA cup can any English club from 5th down aspire realistically to win?
Winning a competition is irrelevant to the skills a manager such as Moyes possesses.
If Moyes was given the transfer budget equivalent of any of the top 3, then yes, winning something within 3-4 years should realistically expected.