Lindelof is not British, was bought from a non-British club, is first choice for his country and cost 35 million. Therefore, if Mourinho was to buy him, it should have been as an immediate first team player, not a developmental one.
In any case Darmian and Blind, and maybe either Rojo or Young, should have been sold when he was bought.
And most certainly, Lindelof should not have been played at RB over Tuanzebe (or TFM had he not been loaned), certainly not in the cup v Derby where Blind was played at CB. (Victor should have started at CB with Axel at RB.)
Tuanzebe and TFM should not have needed loans given how much more gifted they are than Nicky Butt and the Nevilles ever were (except G Nev's stamina).
ETA: Given Tuanzebe was much more impressive than Lindelof when they started together v Swansea, and also not forgetting his nullifying of Sanchez last season, I think it's fair to say he should have also been given more chances (if Lindelof deserves a chance to put a poor performance behind him, why doesn't Tuanzebe deserve one to kick on from a great performance), and the only reason I can think of Lindelof being preferred, especially at RB, was that he was a purchase.