Manchester United could have been the club to sign Gyokeres from Sporting CP, but since he made it known that he wouldn't join Manchester United, that made Manchester United not to enter the race to sign Gyokeres, and that's also the reason why Arsenal was able to sign Gyokeres. Arsenal was very serious about signing Gyokeres, but since Sporting CP used Manchester United to raise Gyokeres's transfer fee, Arsenal found it difficult to meet Gyokeres's transfer fee fast.
That would have made more sense in a multiple different ways. Amorim and Gyokeres meeting up again would have made a lot more sense and I am sad to see them they are not doing that. It's really complicated situation because Gyokeres really wanted Arsenal, not entirely sure what the exact reason was, but there was nothing United could do, the player just wanted to go to Arsenal so what could have they done?
There aren't that many strikers that they could have gotten. Osimhen was one, but he required a lot, he wanted a net of 12+ million euro for his fee, which means 20+ million with taxes, so that has to be the most important part. We need to realize they can't pay that much for the sake of salary balance between players.