I don't disagree with anything you said.Why worry about his long term future? He's 21, first year of a lengthy contract and could easily spend over a decade here, his long term future is far less important than his immediate future.
We have 5 centre backs and no left back in the squad he's one of 2 left footeed defenders and has experince out there. He is primarily a left back option for the foreseeable. It's also an easier and more forgiving introduction to a new team, a new league and a new style. Peps handling him brilliantly in my eyes.
I in no way worried about his long term future, because quite obviously he is talented and it is at the club, I was specific in talking about at left back.
Now you said it doesn't matter if its not at left back as he simply needs minutes, and that's true, but that isn't my point in any way.
My point is, what is Pep's long term future planning?
Is this the ideal he is looking for? Not for Gvardiol, but for the squad, and what does he envision as Gvardiol's role in that future, the Stones role, CB in a back 3, this false kind of fullback he did today.
These are just what I ponder, it's not really anything I would classify as "worry".
Like I already mentioned, Gvardiol was great today, and I have been happy with him this season.
Perhaps Pep himself doesn't even know what he envision as Gvardiol or even City's best set up.