To me this is a matter of degree and not absolute.
So it's not "if gain pleasure (or benefit) then not altruistic" and black and white but rather that someone can be altruistic and gain pleasure at the same time depending on what they are gaining and losing specifically.
So a billionaire giving $100,000 for a good cause might seem to be less altruistic than a person with $200,000 net worth giving $100,000 of it for a good cause.
(Fwiw I've never taken a philosophy course so this is just my personal common sense opinion..)
Formation de K. Matthew Dupree Tufts University Master's degree, Philosophy
2012 – 2013
University of Central Florida Bachelor of Arts (B.A.), Philosophy and Religious Studies
2007 – 2011
University of Central Florida Minor, Mathematics
2007 – 2011
In the article, he could have simply acknowledged PG's essay for re-igniting his critique of Wittgenstein. And, as a bonus, a blog title of "Why Wittgenstein is sort of wrong about philosophy" might have attracted more hits.
Ethics - Are people really altruistic if they gain pleasure from it? What does altruism mean?
Epistemology - what does know mean? (Yes, he's completely wrong, a whole chunk of epistomolgy is about the meaning of what is a justified true belief)
I didn't read any more. No idea who he is, but he doesn't seem to have studied first year philosophy.