for now, barcelona is one of the clubs with the best squad in the world so if they intend to buy players again, it's just a waste. What Xavi has to do right now is focus on making the current squad work very effectively. they must be able to at least win a domestic trophy in the following season and the UCL is one of the trophies that Barcelona must target.
If I look at the world club ranking, Barcelona is ranked eleventh. Although this does not describe the strength of the team, but at least you can certainly think again to call Barcelona the best club in the world. The current number one is Man City. So if you want to judge then you should be in a neutral position. I think the season Man City in the Best Club in the world.
Source: https://footballdatabase.com/ranking/world/1