People keep making this sort of claim and friends seem to have a lot of anecdotes backing it up. But I don't think all college experiences are like this. In college I had a fair number of professors who seemed to delight in arguments going against their ideas. This was especially true with the philosophy professors although the phil professor I interacted with most was an expert in philosophy of science who had a physics degree so that may be relevant. (She did come out of the semester apparently worried that I had a gambling problem because in a discussion about probability related issues I corrected her on what the valid bets in roulette were.)
I spent the majority of a semester arguing with a philosophy professor over epistemology; I undoubtedly came out of that as her favorite student of the year, but likely only out of appreciation that I was the only one in the course who actually understood the material well enough to actually have an opinion.
Link.
Given the positive reactions, I think the professor seeded them with a positive impression of the site's content.