Its difficult to judge Ole Gunnar Solskjaer as a Manager, or put a verdict on his abilities in that role tbh.
He has not been in the role nearly long enough to be judged and his capabilities to steer Man United back up where they belong depends on a number of factors starting with
a) given FULL 100% backing by the board - OGS needs this. If he is to have any impact at the club he needs time, time to 'fix' things. Many personnel are either over the hill, approaching an age where they should be moved on or are simply not good enough to don that shirt for United. On top of this, he needs at least another 2 complete full seasons to be allowed ample time to 're-build' MUFC from scratch, and forge a new side capable of mounting serious title challenges against City and Liverpool. Whether he is given this time depends on the fans patience, and of course the backing of the board. If hes given ample time to get rid of the 'rot' and 'fix' things, he needs FULL 100% backing of the board, without letting anything else ( including qualification for CL ) get in the way.
b) The Quality of his think-thank, bench and advisors - These people do matter ! Sir Alex Ferguson's right man and Co earned their wages at MUFC just like everyone else, they played a pivotal role in supporting and advising SAF in ensuring Man United were serious contenders for the big trophies year in year out and also in making sure they WON stuff. Ole Gunnar Solskjaer will almost defo need the same sort of bench that allowed Fergie the luxury of sitting back and not thinking 'too hard' about what to do when a goal down in important games.
c) Team Spirit - he needs better personnel at the club imo, when i say better I mean players who can adapt and quickly learn how to play like a world class team together. The players need to be playing for each other, not for themselves or trying to justify their wages by relying on their personal reputation and name. They need bring in 5 or 6 new players who are noticeably world class ahead of next season who can 'slot into' the side and improve it 10 fold.
These 3 things for me will improve United and most importantly be the defining factor in deciding whether Solskjaer stays or leaves.