Schmeichel was speaking as a pundit on beIN sports, where he talked about his old club.
United have been impressive since sacking Jose Mourinho two months ago.
But Schmeichel believes one old boss they could regret sacking is Moyes, even though he lead the team to 7th place a year after they had won the league title.
"I think we should have given him more time, accepted that results weren't going to be what we hoped and playing would have been a little different.
"I believe he would have grown into the role. He has the personality and the understanding. He had so many things to learn and no one to learn it from.
"He was left to run the football department on his own. From the club's perspective we should never have dismissed him."