You'd be hard pressed to count worse defensemen on one hand in the entire league who play regular minutes. For players who've played 250 minutes or more Zaitsev ranks 498th in SCF%, 506th in CF%, 506th SF%, and 469th xGF. Basically the only Dmen who rank below him are all D for the Rangers.
The numbers don't lie. Look at Zaitsev's partner's stats with an away from him. Its night and day and that's been the case for his whole career. Anyone who doesn't see this just doesn't want to and are lying to themselves are just straight up don't know hockey.
Zaitsev is one of the worst players in the NHL and that is an irrefutable fact.