But anyway you are right that Manchester City can give their team a boost by signing Wirtz. Because Manchester City now needs new players. Kevin De Bruney may also could leave the club for next season and Rodri is also injured. So signing new players in winter can give a lot of boost.
We should stop exaggerating players' market values; Wirtz isn't worth anything close to €100 million yet; he only had one good season and a good performance in the EUROs, but he hasn't done much this season to justify that price tag, and Bayer will not let him join another team in the middle of the season; what Pep desperately needs is DM backup for Rodri so they don't have to rely on him too much.