Jester David
Hero
4e is different from PF, but I imagine a lot of people swapped from 3e to 4e, found they disliked 4e, and moved to PF. Or back to 3e.I was in the questioning side, at least somewhat. My reasoning was that the games are just so different.
But, first, it would be silly to claim the number is zero, and I won't do that.
And, second, you do make me realize I'm probably too into the weeds here.
At the most casual of levels, it is completely true to say that 4E, PF, PF2E (and 5E etc if you want) are very much the same game fundamentally.
Tell a story. Try to do something. Roll D20, add something, compare to something. Repeat.
If you roll a 17, odds are you did good and if you rolled a 3, odds are you did not. So if you are a very casual player, the GM will play a much larger role in the "fun" than the game being played. (I'll 100% being a mechanics wonk and "WHY" you are adding this not that matters to me, but I'm an outlier. I'm sure I'm an outlier in ENWorld, and I'm sure I'm in much closer company on ENWorld than in gamers worldwide)
But there are probably more than a few mechanics agnostics who migrated from 4E to PF. And probably a fair number who simply followed their GM.
But even for someone who is completely mechanics agnostic, the feel of a game will emerge over tens or scores of sessions. (or less). That is why some games are more popular than others. I predicted 4E would drop off over time as the feel, the patterns emerged. It did. (No issue with people who love that feel, just nonjudgmental predicting the broader trend). We are already seeing that as much as there are people who really like PF2E, there are also those who get turned off, and a lot who just become "meh".
I wouldn't be surprised to see a nice Paizocon spike. But it would change the flow of the river.
But, as you say, the similarities between games really depend on the sample size and other games compared. Comparing 2e, 3e, 4e, PF, and PF2 and the games seem pretty different. When you add Fate, Shadows of Esteren, Vampire, and other systems to the mix the d20 games have a lot of overlap.