Its not really as simple as that. Center back partnerships are down to chemistry, continuity and of course consistence. The problem Ten Hag had is sometimes Lindelof is fit, then he's not. Sometimes Varane is fit then he's not. And Licha thought he was fit, but really he wasn't.
The problem with this is that no chemistry can be built and as a result no continuity. I believe that's why ten hag just stuck with Maguire even Varane when fit, because there was a situation where Varane couldn't be trusted to maintain fitness. Lindelof needed surgery and Martinez of course needed recovery.
Ultimately that causes a headache for any manager and I don't deem this a Ten Hag issue. It most certainly affects preparation.
Against whom? Also worth noting that bringing back a single player won't be enough. But a collective of Shaw, Licha, Casemiro, Eriksen all being available is a much bigger deal, which we frankly haven't seen.
And that's where I agree ten hag takes blame. He should beat Palace, Bournemouth and Forrest for example. He had enough quality to do so.
I am in full agreement that the points tally isn't good enough. But I'm also saying you are underplaying the impact our injuries have had.
I also think a manager should have room for making his own mistakes. At our club a manager can't though, because theres too many other issues.