A couple notes on this:
- The study compared a general US survey with a survey done at a porn expo. It didn't find (and couldn't have found) a correlation between "more porn = more progressive," just a comparison with porn expo goers
- They asked 4 questions about gender roles. Porn convention attendees answered significantly more progressively on 2; when controlling for other variables, only one remained significant.

We found that "porn superfans” are no more sexist or misogynistic than the general U.S. public on two of the four measures (women in politics and women in the general workplace) and held more progressive gender-role attitudes than the general public on the other two measures[, traditional gender roles in the family and affirmative action for women in thef workplace] .

So in my opinion, the Reddit user's headline overstates the claim, but the researchers still wrote in their abstract that

Our results call into question some of the claims that porn consumption fosters de facto negative and hostile attitudes toward women.

Tl;dr- Porn might not make viewers statistically less sexist, but it sure doesn't seem like it makes them more sexist, so kill the puritan in your brain

we're definitely not in a recession, guys