I think Mourinho is done as a coach. He has failed to adapt to playing style and overall locker room atmosphere in today's game. You will not get players that will sacrifice everything for your tactics in today's game unless you're a charismatic/fun coach like Klopp/Simeone. Most young players nowadays will tell the coach to fuk off if they tell them to stay in only one side of the pitch/never move forward/only cover one player.
True, player attitude shift has probably been his downfall, along with an inability to play high pressing, attacking football.
I will say though that Mourinho at his best was equal to Klopp at his best, if not a bit higher. Simeone for me is not in the discussion. He loses too much, even when he has advantage. Mou's achievements in making Porto win CL, dominating SAF and United in the PL for 3 seasons, and then treble with Inter are a very impressive resume.
Only Guardiola and maybe Zidane have had a higher peak as a manager in the last 20 years.