We have Foden, Bernardo, KDB, Sterling, Mahrez, Gunodgan, Torres, Jesus. We don't lack for creative attacking players. We spent £100m on Grealish, and nothing on a defensive midfielder, centre-forward or left back.
You tell me what attributes Grealish has that players like Foden, and Bernardo do not. What is the £100m adding to City's team? It doesn't make sense to me because he wouldn't be in my starting 11, were everyone fit, and a £100m players should be one of the first names on the teamsheet.
When Foden and de Bruyne are fit, does he start in your side? Perhaps answer it that way. If he doesn't, then it calls into question his signing.