Sure, but I note you carefully avoid touching the elephant in the room:
When the official playtest began in fall '18 it was abundantly clear WotC had a huge huge HUGE success on their hands.
Why do we see essentially zero traces of that edition in PF2?
What you're not explaining is how come PF2 feels like it's been developed in total isolation, like a time capsule?
If Pathfinder 2 had been released in 2009(?) at the latest, when it was still possible to claim 4E was the next big thing in ttrpg gaming, I would have had no questions, completely understanding where Paizo came from and what they aimed for.
But ten years later?
I wasn't avoiding anything. I already explained that in my first post.
They wanted to create their own game.
If you want to create your own thing, the last thing you want to do is copy what the industry leader is doing, irrespective of their success. Which begs a rhetorical question I have already raised: is it better to design the game that you want to create, or the game that will be successful (assuming you can have only one or the other)?
I think that Paizo chose to make the game that they wanted to make and then hoped that it would be successful. And, again repeating myself, we have no idea what Paizo's idea of success looks like, so we have no idea at this time whether or not Paizo achieved success with PF2. It might be an astounding success for them. It could be a miserable failure. It might be just barely good enough. We can speculate based on the limited data we do have, but we lack sufficient facts to "know".
For better or worse, I don't think Paizo relied much on what other designers had done. I think the reason you say it feels like it was developed in isolation is because it was.
There are two theories on reading as it pertains to being a writer. The first is to read everything you can so as to assimilate many ideas and writing styles; to see what and how the competition is doing things, as it were. The other is to avoid reading anything else in your genre, because outside ideas might pollute your own creativity and style, and your books might end up less original as a result. Both are legitimate approaches as I understand it, but it depends on the individual as to which approach works better for them. I think Paizo was going with more or less the latter approach.
Obviously, given that this was a collaborative effort, at least some of their designers were familiar with at least some outside games, but PF2 doesn't look to me like a game that was designed by borrowing pieces from other games. I think that its similarities to 4e can be attributed to convergent design that was a result of both teams trying to address issues they had with 3.x/PF. If you lay out the 4e books next to PF2 and compare the actual implementations, they are quite different. Which suggests to me that PF2 was a "second evolution" of the 3.x ruleset, rather than intentionally made to feel similar to 4e.
