Mathieu was pretty crap overall, come on. That list is mostly terrible. Let's see Christensen and Araujo.
Mathuei was great CB in 1st couple of seasons who was atrocious when played at LB, last season he was bad but didn't leech money after and happily accepted a move out. Also he had few injuries in 2016 iirc
I remember many times during first season many here debated whether he ir Mascherano should be starting CB.
The List really doesn't say whole thing tbh
Barca wasn't after a starting CB between 2009 and 2016 tbh.
M
We had Puyol & Pique and then Mascherano step up until we decided to go for starting CB with Umtiti in 2016 and he was success.
Chygrnsky was awful considering price tag, but Mathuei, Vermaelen & Murillo were stop gap veteran CB
While Araujo (and many others B team signing) , Mina and Todibo were young gambles that mostly worked fairly well (either through sales or Araujo stepping up)
Even Lenglet was signed as overpriced back up CB.