For players like Rashford, the arrival of a new head coach at Manchester United is a great chance to prove himself from the best side and become a player of the foundation of the club. If the player stayed at the club, then let's hope that he already had a meeting with Ten Hag, where he gave him some hope. The previous coach may well have had his own preferences or simply the player did not fit into his game scheme, but now everything should be new and everyone has chances. I would really like this undoubtedly talented player to finally find himself and begin to justify the advances that have been assigned to him for quite a long time.
Compared to previous seasons, the last one was certainly a failure for Rashford, although he had enough games to prove himself. But Ten Hag has already said he's not interested in getting more attacking (in terms of transfers) at United, he's just looking for a stronger game from existing players. I think this means that he understands his potential and believes that with the overall progress of the team, Rashford will be able to return at least to the previous level.
This is clearly one of the advantages because indeed with Ten Hag not being aggressive in looking for players, this is clearly a pretty good opportunity for the existing players.
Rashford's form this season hasn't gone well as the difference is clear compared to his previous form but maybe now with Ten Hag's cool hand he will fit in and hopefully like that.