Tbf Xavi's signings here were much better than Ten Hag's signings at United.
However, the question is, how much of United's transfer business issues are because of the wrong targets, or a lack of pull? Here, Xavi brought Raphinha, Lewa, Kounde, Gundogan etc, but at United, I really doubt they will be able to attract such players. I think they were also in for Raphinha but he ended here, and then they went for Antony who is of course much worse.
So he will have much more money, but will have to aim a little lower in terms of how ambitious he can be with the targets. Therefore the talent ID and scouting will have to be a little more important and they still might have to overpay to get players he wants.
Xavi also I think has a certain pull of his own and players might be excited to join the rebuild so that would help.