I found the same news, Barcelona will not buy new players. Maybe they will maximise De Jong and the existing players. Regarding Gavi, I think it's not the end of his career because there is still a chance with his ACL revamping. Maybe a little longer, but I think he can come back to play. Even I also have ACL at this time. Even though I wasn't a professional player, the ACL kept me from doing my best in football because I didn't have surgery to repair the injury. I know how painful and sad this injury is. So hopefully gavi gets well soon, he is still young and his recovery will be faster.
We must understand that Barcelona isn't in a good condition of their financial stability. So, it makes sense if they won't plan to buy new players in January transfer window. Actually, Barcelona has some good midfielders, besides Gavi they have Frenkie de Jong, İlkay Gündoğan, Pedri, Oriol Romeu, and Fermín López. I think the number of Barcelona midfielders isn't very small, it is enough for the whole of the season. Moreover, Frenkie de Jong will recover soon, so Barcelona only has 1 injured midfielder. It won't be a very serious problem for Xavi, he can replace him with other midfielders. However, we expect that Gavi won't get injury for a long time.