It's interesting... his site has plenty of valuable info but only if you're knowledgeable enough of a photographer to identify what is his opinion vs. what's an objective criticism.
Yep, I know a small bit about photography and Ken's advice is better than most. One of the few places where you will hear that some product isn't worth the money, and here is a different cheaper one that's just as good. Or that here is one that is much cheaper and most people will never notice the difference. That's very helpful to the mainstream photographer, and very rare to see.
He is not the "Stereophile" type of reviewer, for example.
And this is such a good example of why single-person review sites are not the answer to the problem. The site is in theory most useful to people who don't know much about the topic. But to know that the site isn't credible, you need to know a fair bit.
One solution is things like Consumer Reports and Wirecutter, where you have an institution that does some quality control. But I wonder if there's something in the middle, like a few good reviewers clubbing together and certifying one another, such that there's a recognizable brand that they share, one with meaningfully high standards.
I've actually found some of Ken Rockwell's info on analog cameras (especially Leica & lenses) to be super helpful, but I can't speak to his digital knowledge. Also, his photography itself isn't great.
There's value but you can't just read one article. He contradicts himself. One post will rant about how digital means you don't need a tripod then another will be a glowing review of...a tripod.