All legitimate questions, Retreater, but you have to turn it around too: other people run successful XYZ campaigns, and have had time to do so repeatedly now. So if the problem is with the game, how do they do so?
You can say that about almost any XYZ, AD&D 1, AD&D 2, D&D 3.0, D&D 3.5, D&D 4, Pathfinder 1E, Rifts, Palladium Fantasy, etc. The problem is always between the game and the players, but that doesn't mean the game works well for certain, many or most people.
I'm running the Agents of Edgewatch now, and it's not working for me.
On the good side, I like the three action economy. I haven't really built PCs with the system, but I like, at least in theory, the generalizing of feats.
On the bad side, some of it may be my particular group of PCs, but battles are long and grindy and boring. There's more than enough healing for the PCs to outrun any battle; maybe because the earlier levels were occasionally deadly, the PCs have adapted to turtle at level 12.
NPCs aren't built like PCs any more, but that doesn't necessarily help; instead of knowing what a rogue can do, each enemy has bespoke powers. Last night's adventure even had stupid ones; it's a 12th level adventure, why do the NPCs have powers that only work against 11th level or lower characters? I wanted easier to run monsters, but PF2 is not delivering.
The removal of most of the must have magic items, like attribute boosts, doesn't seem have to made magic item choices any more interesting.
It's a somewhat minor thing, but the attribute part of character creation is grossly complex, for what value? If you're worried about minimaxing, give me a stat array, or a choice of a couple stat arrays, and go on.
For the ugly, maybe I haven't learned it well enough, but I feel I've taken a overly complex, crunchy game system I knew, and traded it for a overly complex, crunchy game system I don't know, a jump quite a bit bigger than D&D 3 to Pathfinder, and for little gain. For example, the XP system was changed; why? The book doesn't really help you learn it, from anew or just the differences; the skills section started on page 243. Yes, PF1 was like that, but it was close enough to 3.5 and by now I know PF1.
I've talked with a couple players, and we may jump ship, probably back to PF1, or maybe try out Starfinder for a while.