Pathfinder was the top-selling role-playing game in the second quarter of 2011,[9] autumn 2012,[10] spring 2013,[11] and autumn 2013.[12] It replaced Dungeons & Dragons, which had been the best-selling game since 1974.[13]
You're conflating sales with play time here. Just because it sold more copies in four quarters more than a decade after 3.5e was released doesn't mean people play it more often; most of the people who would play 3.5e already have their books or know someone they can borrow from.
http://www.d20srd.org/
Which has maybe 3% of the total of 3.5's information. Base classes, psionics and some "alternative classes". There was DnDTools, but that got a C&D. Compare that with the D20PFSRD.
Other than this guy, I have not seen a single group playing 3.5, since it's been replaced in every functional way by Pathfinder.
I take it you haven't been to our FG&RP or Play With Your Buddies boards... well, ever. We've got I think two 5e campaigns, two 4e campaigns, around 15-20 3.5e campaigns (plus a dozen more at any given time that don't get off the ground), with most of the latter being houseruled, and precisely zero PF campaigns.
My uni isn't exactly a roleplaying Mecca, but of the group adverts I've seen, one was looking for players for CoC d20, one for 5e, and two for 3.5e.
Given how hard you're pushing PF you're probably heavily invested in the idea of it being the very best that ever was, and if that's the case you're probably only playing with likeminded people in communities of such. Though you haven't even bothered to provide
anecdotal evidence of your claims, just meaningless sales.
E: aaaand, when you come right down to it, I said it already: PF is 3.5e with a set of houserules some people liked enough to pay for.