Of course Jose was right about a few things, notably the problems with the club's structure and decision-making, and his assessments of a few players. But he was also wrong about a few things, made an array of mistakes as a tactician and as a man-manager and when he got sacked it was thoroughly deserved.
In Mourinho's defence, the rebuilding job he was tasked with was possibly the most difficult since Fergie left as the squad Van Gaal left behind was an utter mess. I never really expected him to win the league given he was playing catch-up with City but for the money spent I'd have expected Top-4 in his first season and a much better showing in the Champions League in that second season. Looking at the players who came in, I honestly think you'd struggle to point to an area of the squad which was noticeably stronger in December 2018 than it had been in Summer of 2016.