It is important for Manchester United to get their game in order before thinking about achieving higher goals, because they still look very weak against strong opponents. As for Amorim's work, it seems to me that he pays more attention to working within the team with the players, as an example, the absence of Rashford, which indicates that there is no order within the team, maybe he is trying to work with the players, because I do not see any changes on the field at Manchester United.
In the Europa League, Manchester United's performance has indeed improved slightly compared to their performance in the Premier League so that many people doubt Manchester United's performance to compete for the title because there are still many weaknesses that Amorim has not been able to overcome. He is strict with the players and even previously Garnaco and Rashford were rested because they did not show a good attitude when working with their teammates, although in the end Garnaco was played again. But especially for Rashford, he has a much bigger problem and rumors are that Manchester United are ready to let him go if an offer comes in.
This isn't really surprising considering they are one of the better teams in this league, or at least they should be, they are just not doing worse than expected. United actually has a possibility to win the whole thing, I am not saying they will, I am just saying there is a chance they could do that.
In the end, we are talking about having something that will change if they face a team that shockingly beats them. They were in Europa a few seasons ago too, and lost eventually, so something like that could very well happen again. But aside from a shocking result like that, expected result for them would be going deep into the season and potentially even maybe win the whole thing. Of course it is not easy and I understand why people would have second thoughts about it, and betting on them is not easy neither, but that doesn't mean that we are going to end up with easy solutions neither, it just doesn't feel like we are going to get anything good out of it.