I did not read the last page of the thread, but in the first two pages I think that there is a concept that no one is talking about.
I have said for years that the real difference between Paizo and WOTC is that Paizo's real focus is on the adventures. The adventure paths and the modules (also world building) are the real income stream that Paizo has on a monthly basis. PF came about because of 4e, and the change in the OGL to the GSL which was more restrictive, and could be pulled. WOTC's focus is on the rule books, and they do adventures to support that. Also, WOTC's adventures reach back into the past and rehash old material over and over. Sometimes this old material changes as part of their rehash like the current Temple of Elemental Evil book, sometimes it is just updated to the new rules. Do not get me wrong, I love my favorite ideas being updated. I like the rehash actually, but the focus of the companies are totally different.
Paizo does not die out if they stop creating new rule content because they continue to build the world, and create adventure paths. I also usually like what they have done with the rules, although there are more options than I will ever get to explore now...
I understand the appeal to 5e, I have not played it yet, but I still play 1e with my son from time to time... The simplicity of the old rules combined with some modern ideas of gaming is what appeals to me about 5e. I like the idea of faster combat, and as the DM not having so much happening to really play the NPCs and monsters to their potential.
Going back to a monsters that do not have feats or skills, and a simplified skill system, and feat system appeals to me, without THACO and some of the other things that were tough about the early game.
On the other hand the material I am running right now is in Pathfinder, and I am too busy to spend hours converting adventures to another ruleset.
So I think the differing philosophies of the two companies has a lot to do with the need for PF 2.0.