I mean, that was the intention. It was designed specifically for the 3.5 people to have more 3.5 to play after WotC decided to move on to 4th edition. That was the entire goal. There was also a big OGL scandal because WotC was trying to make an proprietary in-house VTT with 4e's rules coded into it, and as such they needed the rules to be legally Theirs. Paizo was in a place to take advantage of that misstep, and so they did.