I don't think PF2 was quite the success on launch that Paizo was hoping for. But it is clear that PF2 is now attracting 5e players willing to look for something more, and it is finding its feet on VTT platforms not roll20.
Genuinely wonder how much of that is down to a combination of:
1) Early AP issues. Age of Ashes is notorious now for its difficulty. Having your first major adventure be so difficult was probably not a wise decision, especially when the game requires a more tactical mind than the main competition. It would have been wiser to be much more of an ease in campaign.
From what I understand, Extinction Curse did not have quite the same issues, but it might have somewhat gotten off theme a bit too quickly, and it is a less universal theme than soemthing like Age of Ashes.
And then there is Agents of Edgewatch which has quite a lot of issues that, partly due to them being fairly political, I won't go into here.
In my opinion, it probably doesn't help that they didn't get their first three book Adventure Path - in the form of Abomination Vaults - out the door until January 2021. That one has been extremely successful, and while that is also down to the fact that they really improved Adventure Path design by then by all accounts, I wouldnt' be surprised if the fact it is a level 1 to 10 adventure helpful.
2) Controversy over YouTuber opinions. I'm not going to delve deep into this so as to not cause drama, but there were a number of not so kind and somewhat misleading reviews released by some YouTubers early in the system lifecycle that may have scared people away.
3) The Pathfinder community splitting between those staying with Pathfinder 1e, those switching to Pathfinder 2e, and people new to Pathfinder coming in. There does not seem to be the same exodus as there was from 4e to 5e for a wide variety of reasons, so Pathfinder 2e needed to wait longer to attract enough word of mouth and a base to start expanding.