Central defence definitely needs to be improved. However, the reports I've read all suggest that Ole still sees a future in Tuanzebe and Bailly for now.
I think we'll go into next season with Maguire, Lindelof, Tuanzebe, Bailly and Mengi as our options. It'll be last chance saloon for Tuanzebe and Bailly, with no new CBs coming in until January at the earliest.
Hopefully Axel can save us a few bob by nailing down a starting position alongside Maguire by then. If he fulfils his potential, he'll be top class.
The talk about wanting a left-footed centreback is probably about scouting targets in case the in-house options fail to stake their claims.