This is the only statement I will agree. When you compare defenders who play for offensive and non physical team, Thiago Silva, Lahm and Pique are the best defenders in the last years. How much non Barca fans estimate him is not a valid argument. (Eg Busquets)
Pique has very good tactical awareness. Excellent passer of the ball. Proactive defender (unlike Ramos). Has the ability to break lines by carrying the ball forward. The build up towards the second goal in the el clasico is an example, how affective his tactical awareness in nullifying opponent's tactics.
It's remarkable how quickly Umtiti adapted. He too is proactive. He is also good passer. But you cannot compare his passing with that of Pique which Xavi and Iniesta used to rely on. Umtiti's leaner physic enable him to be better in tackles but in most of the instances, Pique would stop the attack so there is no need for him to tackle much. His excellent positioning is unquestionable. Remember that, in certain matches he was a one man defense with a midfielder as RB and a defensive midfielder as another CB. It's no question how much bad Mascherano's positioning is. Umtiti can't even perform at high level along Varane (they two are the best young defenders in the world at the moment). As I said before, we will still remain the best defensive team in the world, as long as we play with Pique, Vermaelen and Rakitic.
And Beckenbauer has said that Pique resembles him. So, he indeed is highly ranked by one of the greatest defenders in the history of football