I'm definitely not going to have high hopes on Manchester United, just like you said, so far they haven't yet met a tough opponent in the competition so far that's why it seems as if they haven't lost a single game. Once they meet a worthy opponent, I think they will definitely snap thereby crashing out of the competition sooner or later. After this round of 16, it will come to the point where only the consistent team is left to battle it out.
Domestically, they are awful but as long as the europa league is concerned, they've not been doing badly. I was actually tipping them to win the trophy but with their injury crisis, I'm a bit skeptical. Their strikers, Hojlund and Zirkzee have not been performing up to par and one of their best player, Amad, has been ruled out of the season which makes it even tougher for them. If they win it, it would really be a miracle.