Lot of that isn't true though is it. Firstly, the manager has barely anything to do with moving on players, if you want someone to praise for that go look at the usual suspects for criticism - Woodward and Judge. Quality of football has barely improved at all on Mourinho's second season, and is getting worse not better. Performances and consistency have been atrocious this season, like they were for the previous season before Bruno arrived. Signed Bruno yes, but also signed AWB and Maguire, massive wastes of money on players who don't remotely fit the profile Ole should have been looking for given his tactical preferences. Made Maguire captain, another big mistake. Bottled out of every cup competition. Bottled out of the CL group stage in hugely embarrassing fashion. Currently on target to not improve on the points haul from last season.
A couple of players have improved in the last two years, like Shaw, but is that because of Ole or just because they're playing regularly and avoiding injury? Pretty fair bet it's the latter. Meanwhile, why have the players everyone expected to improve under Ole - Rashford and Martial namely - either stagnated or massively declined.