Springer Nature’s Dagmar Laging, in an inteview for the Scholarly Kitchen:

But with not only transformative deals but the need to secure sustainable funding for fully OA equally critical to supporting the transition to OA, it was important to us and Projekt DEAL that any solution encompassed both hybrid journals and fully OA journals.

There are a host of problems with read-and-publish deals like this, notably around North-South inequalities (even within Europe). But the effective lock-in of extortionate APC levels and the preservation of hybrid journals are terrible too.