Pep's system is reliant on a player like Busquets, Javi, Lahm etc. They don't need to be pacy or a Fernandinho (Re; why they went for Rodri after missing on Jorginho), he made that adjustment when he came to England because a ready made all in everything Fernandinho was just available. Let's not act like Fernandinho's first year under Pep was something to remember either, people have short term memories it seems. It just happened to work out in time.
The team is unsettled without any pre season and large number of injuries, if we get a left back, we will revisit this and you will see.
This all looks like more than just doubts have started to creep in about Pep's ability and what he wants, quite interesting.