Barcelona is experiencing a certain chaos in transfers, but this is less about Xavi and more about the fact that the club has been on the verge of bankruptcy for the last couple of years, so even if they make the transfer they wanted, they cannot impose their conditions. As in the case of Dembélé, for example. Barcelona is now far from being an attractive club for good/near top players and all the problems come from this (naturally, unresolved financial problems also have a negative impact).
Other than some players Barcelona is trying to hire for their teams, I think should try harder to keep the player they currently have in the team.
For example, currently, Clément Lenglet is seriously close to leaving Barcelona for Bayern Munich and is linked to this team.
He is currently playing at Aston Villa on loan while Bayern Munich wants to hire this French player and improve the team during the winter.
Yes, I wrote a long time ago that there is no point (if I were Barcelona) in trying to maintain the same level of expenses as successful top clubs until they sort out their financial problems. If they fail to sell Lewandowski to Saudi Arabia, then in fact his transfer will be a super failure. Barcelona could well play for a couple of years relying on its academy and young players, but no, Xavi is always trying to buy someone, but due to the salary cap and deteriorating image, Barcelona does not get the best options. At the same time, as can be seen from your example, promising players can be lured by other clubs.