well i obviously dont watch every game. My basis is on a few things. Articles i have read particularly from draft sites that do extensive research of these prospects and those sites agree parker is a defensive liability and wiggins was not. Secondly i routinely visit an basketball chat forum (not this one) that talks about all kinds of players strengths and weaknesses and from what ive read there, the people seem to agree he is a defensive liability while wiggins is not. And, just so you dont think im full nothing more then regurgitating others opinions, i have seen both guys numerous times throughout the year. In fact when ucla (my team) played duke at madison square garden this year, kyle "slo mo" anderson blew right by parker one on one a few times with no screen whatsover. Just crossed him and got all the way to the rim. In fact the other chat site i visit even created a thread about how parker couldnt stay in front of anderson just as i was watching it.
So how do you justify Wiggins having a worse defensive rating and defensive win shares despite playing more minutes, with better defenders, on a better defensive team? And quoting a bunch of draft experts and amateurs about how they project to the pros doesn't help your claim that Jabari was a bad defender by college standards. Jabari was a bad college defender while Wiggins being elite just doesn't show up anywhere but the "eye test".
As a freshmen, Wiggins' defensive metrics were behind Jeff Green, Corey Brewer, Harrison Barnes, Rudy Gay, Perry Jones III, Marvin Williams, Andre Iguodala, Kevin Durant, Tony Allen, and Michael Kidd-Gilchrist despite being one of the top minutes getter between them. Most of them also didn't have an elite rim protector behind them. That group doesn't include other top wing defenders who didn't play in big time conferences like Paul George and Kawhi Leonard.
Yes, Wiggy is fast, quick and long. He has all the tools to become a great defender, but there are plenty of those guys in the NBA who blow at defense. Wiggins is crap at fighting over screens and gambles on passes getting himself out of position. Wiggins is also crap at recovering once a guy gets a step on him, despite his speed. He also has terrible jumping technique in traffic and doesn't alter shots the way he should. These things a are all coachable (except the lack of effort on recovery), but the jury is still out on whether he does it.
Parker for all his shortcomings is big, strong and a good jumper on the defensive end. He doesn't move side-to-side well but he reacts quickly to the people around him; he goes to the right spot more often than not. His help defense is on a different stratosphere than Wiggins in college. Around the rim he alters shot better than Wiggins does, partially because of him defending the post the majority of the time but also because he makes himself bigger than Wiggins on those shots. He probably can't get much better than he is now unless he has a lot of untapped potential in his lateral movement.
