Re Wilson: the games you mention were all poor performances...but that's only 5 games, and you've named 4 of our 7 defeats under him that season.
Of course the football was defensive. United scored 92 goals the previous season. Evans was incarcerated (29 goals gone) Williams wouldn't re-sign (13 goals gone) Lowton was sold by the board (6 goals and an excellent defender gone) Quinn was sold on the cheap because of his wages (3 goals and a key midfielder gone) Matty Phillips had only been on loan (5 goals gone). That's 56 goals you need to replace, when the club's budget was being reduced, not increased. Plus Cresswell (9 goals) was done, and only scored once. How are you going to replace all those goals when the club is in sell mode?
Wilson tried. He brought Blackman in, who did well (11 goals) and he was sold on the last day of the transfer window over Wilson's objection. He brought Kitson in, who did ok given his age (11 goals). Shaun Miller looked good but got injured at Christmas. Wilson was only able to scramble around and bring in Forte and Poleon at the end of the window. Both were useless, scoring once in 19 games combined. Joe Ironside was tried but was also useless. You mention Carlisle and Crawley - Forte effectively got Wilson fired as he was almost single handedly responsible for United failing to win those games thanks to a series of appalling misses.
Meanwhile, we were more defensive because we had a good defence. Maguire was excellent. Collins was excellent then (no one will give him credit for it given his form later but he was). George Long played well. We conceded only 36 goals in the 41 games Wilson managed. That's excellent. We didn't lose till November. Things were not perfect, but we let Wilson go with United in the playoff places. He'd done a good job.
Deserved to be fired? McCabe was asked at the press conference introducing Morgan as caretaker why Wilson had been fired. There is a video of that somewhere. McCabe was unable to give a cogent reason for the decision. The best he could do was to say we hadn't been winning at home. No we hadn't. 3 0-0 draws and a 0-2 defeat to Crawley, thanks to Forte. We declined under Morgan and ended up being away for the second leg of the playoffs, sealing our fate.
Re Clough: whilst he was his own worst enemy, he left us after a season and a half having achieved the following:
He took us to 2 major cup semi finals. No third tier club has ever achieved this in consecutive seasons. Only one (Wycombe) has ever done it at all. We beat 6 PL teams in Cups, 4 times away from home.
He took a team that had won one of its first 11 games and had 5 points into 7th place
He led the team to 10 successive victories in all competitions in 2013-14. This run inculded a spell of 7 straight league wins without conceding a goal.
He took the team into the playoffs into his second season. Should he have done better? Yes. But at the same time it's not nothing.
Clough is a flawed manager. 2014-5 was extremely frustrating in the league to say the least. I was glad he went. Wilson was a flawed manager. He should have done better in 2011-12. His recruitment could have been better in 2012-13.
But Gary Speed was manager for league 18 games, winning 6 and losing 9. How can he be rated better than Clough or Wilson's 2012/13 season?