He won every air duel he was in. Had good dribbling. And stole possession like a champ. Not every DM needs to be offensive. His passing also wasn't that bad. Rotation DM for double pivot is good enough. Not many excellent DMs will accept that kinda position on the team.
No he was weak in a good number of matches then he became acceptable but yet purposeless and unconvincing 15-18 mil player by max and very sub . Not needed. Midfield like real casmeiro, modric, Kroos better . All can play everything from defending to attacking