You would think so, but as long as Guardiola is in charge, it will be harder to fix than you would think. He will always prefer sticking a midfielder at CB rather than buying a specialist defender; that's what he's done his whole career. When that doesn't work, he's going to start sticking full-backs there (Kyle Walker, it's your turn soon). Using a common sense fix for an obvious problem for Pep is like admitting defeat.
Kyle Walker has already had a go there.
I think they'll definitely buy a CB or two in the summer.