We have an exceptionally stupid set of defensive players right now. The likes of Maguire, Shaw, AWB, Fred, McTominay, Pogba when playing in a deeper role etc... these guys all have incredibly low "footballing IQs". To use a hackneyed phrase.
But not only that, the guys who are experienced and have a bit of brains about them are very quiet and meek on the pitch, specifically Matic and Lindelof.
So they're not going to figure it out on their own. They all need extensive coaching. They all need their hands held in what to do during all possible situations and scenarios. But clearly they're receiving no defensive coaching at all. There's no work on team pressing, no work on improving their communication with each other, no work on defensive positioning. No drills.