Kompany and Otamendi are City's highest earning defenders on £120k p/w.
Do you really think Laporte, 23 and coming from a club where he is lucky to be on even half of that, is going to be on £200k p/w - only two players in City's squad are earning this much - Aguero and KDB (as of last week).
As with most players, he'll be on a basic salary of around £80-100k p/w - there may be the slightest chance he hits £200k p/w through performance bonuses if City win a quadruple and he has the season of his life, but that is significantly unlikely.
It's how all of City's contracts work and it was implemented by Soriano, structured in the same way he did at Barca. If the players win everything, they're massively rewarded, if they win nothing, they have a lower basic wage when compared to most top clubs.