Plenty of animators can draw good. Most people can't draw like Hayao Miyazaki, and Milt Gross was above most people with his designs. Many people can draw at the same level as John K, just in different styles. But they don't criticize other people's work and know how to compromise with the "business" aspect of animation. John K, unfortunately, doesn't.
Granted, John K lives in an age where, sadly, the originality in cartoons is becoming less and less. CGI features with recycled designs are pushing out traditionally animated features, and more and more television cartoons are either poorly flash animated or just plain unappealing (not all, mind you, not all). It's enough to make any veteran animator who was around when cartoons like The Flintstones and Looney Tunes were made to be frustrated. Many other people are frustrated just like John K, but John K just ends up putting his ideas into rant form some time. Maybe it just means he's passionate about cartoons.
I find myself agreeing with John K more and more on a wider array of topics, but I still disagree with a lot of what he says. I don't like how he completely loathes all and any anime, and the Disney animated features from the 90's aren't as horrible as he says. But on most topics- design, animation, and what animators should know- John K knows what he's talking about. His whole life is animation. What John K did made a wider impact on cartoons in the 90's than most of us probably realize. He did more than just Ren and Stimpy. Many of the people who he brought into animation with Ren and Stimpy went on to work on shows like Dexter's Lab, Powerpuff Girls, and Samurai Jack. He revitalized creator-driven cartoons outside of sitcom cartoons like The Simpsons.
Also, I have yet to hear any major animator, or anyone in the animation industry, criticize John K the way most people do. Genndy Tartakovsky, Craig McCracken, Joe Murray, Fred Seibert, all respect John K. The man is definitely passionate about cartoons and never hesitates to express his opinion, but the man definitely knows what he's talking about most of the time.