Why feel worry? Gündoğan has only one year remaining in City, but if he keeps perform. City can hand him a new contract.
That's why i won't rush to say he's not able to cover a long season with City. I remind you Rodri is back, and having him in the squad will obviously adding the depth to the City's mid.
Gundudgan will get very limited time next season, because, unlike last season, when Manchester City were left with very few options in midfield, Manc City have made some changes. With the inclusion of Reijiers and Cheki, Gunduga won't be a regular player, except more long-term injuries happen.
Rodri is back, and before the new season starts, he will be fully fit, which means he will take back his role as the DM, with Nico as a backup.
It's normal for age to catch up to players and when that happens you don't expect them to be playing as they used to when they were younger so Gundogan is no different and I am sure he knows he doesn't have much time left with the Club just as De Bruyne left he will leave someday. Manchester City suffered last season because Rodri was absent and the remaining players are getting old so I don't blame them for making recruits and adding more players to the squad. The performance was really bad and new players were really needed to help improve the squad. Well let's just hope the new players adapt easily so they can relief Gundogan of the stress if not he has nothing to worry about his playing time because if they don't adapt early Guardiola will be forced to use him.