This could perhaps be used as a reason and motivation for the Manchester United team in the FA Cup because it is true as you said that only the FA Cup is possible for Manchester United to win this season.
If you look at the strength of the Nottingham Forest team, it is not that strong and it should not be difficult for Manchester United to win this match.
I doubt if Manchester United will be able to lift the FA Cup this season, I count them out, looking at other teams that are in the competition Liverpool, Manchester city, and Chelsea and the rest of other teams that are way better in performance this season than the United team, likely for them they may end up being able to reach the semi-final stage of the competition.
There are many candidates in the FA cup. Im doubting MU can win this title. It was always facing the bad result when mu got liverpool as its opponent. United will have city as its next opponent and i expect that there will be something to happen soon. It's a non sense to favor MU to be a winner this season.
City and newcastle have won the previous games against mediocre club. Haaland itself created 5 goals alone against luton. How can manchester united beat this monster? Statistically, manchester city is far above any clubs in the FA club now. I would rather than pick city over MU to be a winner.
We still have chelsea, liverpool and brighton that will be winning against their opponents. Considering so many strong clubs were able beating their opponents made me believe that if MU has a very hard way to get FA cup this season.
MU is gonna face notthm forest which will not be a difficult opponent for manchester united. The main problem since nottingham may be playing use the defensive strategy and it will make MU struggle to beat it.
Im trying to trust this club but the defensive line and goal keeper have made me lost my trust to believe in united.
There are still many monsters competing with MU in FA cup. The chance is pretty small to win FA cup this time.