They've become worse since Mourinho left. It looks like the dressing room is not that good either. I expect them to go through this phase of uncertainty and the loss of leadership for several years if they can't find suitable players or managers to fulfill the role. Their fans need some patience and stop screwing up the stock price, or United will sink further.
I don't think that Mourinho is the problem.
He tried to build something strong in Manchester United but he didn't make it (I think he was the one who signed Pogba to the club) a decent signing for that period of time. I won't blame Mourinho because Pogba and some other players became lazy and they don't work hard to become better players....