The only rational explanation for me is that Rodri's injury has exposed a number of weaknesses that were already there, and they've since been magnified, especially as we now lose the ball more often in silly positions.
I always suspected that one day Ederson would prove to be a liability but equally not having a single orthodox Left Back, (despite chasing Cucurella a couple of summers ago) is now beginning to bite without Rodri's presence.
Walker and De Bruyne were both showing signs of ageing last season, but it didn't matter because Foden was scoring so many goals. Now he's not scoring any.
Plus what's the point of buying the most prolific goalscorer in world football if we're not even trying to play to his strengths with pace down the flanks and the ball whipped across?
I'm not sure if that constitutes a crisis, but after Villa we've got a run of supposedly winnable matches that will surely provide the answer.