I
am surprised that there are so many posters on LL who can spend the time to read Ken Rockwell's site in order to form an opinion that he is a cretin or a jester, or whatever.
I very rarely visit his site myself, but I have defended in the past, on LL, some of his statements about photography, which can be at least thought-provoking.
Often when people have a strong reaction against a particular opinion on any matter, resulting in ad hominem attacks upon the person expressing the opinion, it's because there is an element of truth in that opinion that is too disturbing to think about.
I get the impression that Rockwell uses a technique of making statements of a general nature that may be true only in specific circumstances which he doesn't always mention, but leaves it up to the reader to work out what those circumstances may be.
To illustrate this point, let's consider some of the examples of Ken Rockwell's pronouncements that the OP has mentioned.
(1) ISO and megapixels are merely marketing ploys.Such a statement is clearly wrong, as expressed and without qualification, and taken out of context. But the statement contains elements of truth which, if expressed with slightly different wording, could be accepted as being wholly true. However, the statement would then not be so controversial. For example, how about,
"High ISO settings and a high pixel-count are a part of a camera company's marketing strategy." Would anyone disagree with that statement?
(2) All lenses are sharp, more so than one could ever appreciate or need unless you're a lens manufacturer yourself.Again, if we modify the statement and flesh it out, we can see there are elements of truth here that may apply in certain circumstances. For example, how about,
"For the photographic novice who never makes prints larger than A4, and who frequently produces blurry shots because the shutter speed was not sufficient to freeze camera or subject movement, and/or the focusing was not accurate, all lenses can be considered as equally sharp. The path to producing better photos is to improve one's technique, not to obsess about lens sharpness".Everything requires interpretation.