I don't think there is any chance PF2 is the game. Not because it isn't good, or because Paizo isn't a strong company, but because it is too complex for the kind of casual players that have pushed 5E to its current heights. A PF3 would have to severely curtail the very elements that differentiate it from D&D, and even then there would be no guarantee of success.
I agree.
I mean, let's be fair to PF2. It's not drastically more complex than 5E in the real nitty-gritty of the rules. In fact, I think if we looked at the whole ruleset holistically, PF2 might be slightly more straightforward than 5E, because its systems work in much more predictable ways, and the classes, ultimately, are slightly more similar to each other than 5E classes.
However... that's not what matters.
5E is accessible because there's a very low bar to creating a character and getting started. It's lower even than some RPGs that are drastically more simple, because there are so few real choices at L1. Further, in combat at low levels, you can barely make any choices, and to call what you can do "tactics" seems generous. But again, this makes it very accessible. Whereas in PF2, with the 3-action system, you can make quite complex tactical decisions, but this does come at a demonstrable cost to accessibility (it also brings back some 3E-style "analysis paralysis" - not a huge amount, but significantly more than 5E - 4E is the only tactically complex system I've seen which didn't make that a big issue - I suspect Lancer is also fine but haven't played it).
I suspect with say, level 8 PCs, and players who've been playing at least a year, the complexity is largely interchangeable, but again, that's not when it matters most.
Remember when Lorraine Williams was canonized as the savior of D&D in the aftermath of Gygax's complete mismanagement on these boards, just a few months ago when Slaying the Dragon was all the rage?
Pepperidge Farms remembers.
I mean, canonized might be going a bit far, but reassessed in a less sexist and "Gygax rules!"-informed way? Yeah I remember. It certainly seemed like a more reasonable assessment. She made plenty of mistakes and engaged in some dubious practices (c.f. Buck Rogers), but she certainly wasn't the devilish figure we were lead to believe she was in the '90s and '00s.