And so instead of denouncing philosophy, most people who suspected it was a waste of time just studied other things. That alone is fairly damning evidence, considering philosophy’s claims. It’s supposed to be about the ultimate truths. Surely all smart people would be interested in it, if it delivered on that promise.
Because philosophy’s flaws turned away the sort of people who might have corrected them, they tended to be self-perpetuating. Bertrand Russell wrote in a letter in 1912:
Hitherto the people attracted to philosophy have been mostly those who loved the big generalizations, which were all wrong, so that few people with exact minds have taken up the subject.
[..] There’s a market for writing that sounds impressive and can’t be disproven.
Alternately, Western ‘word salad’ Philosophy might benefit from a bit of reinventing:
http://www.paulgraham.com/philosophy.html