That doesn't sound very different.
That is because it isn't.
"Different" means many things at once. Where you see being able to explode entire cities, Paizo sees a clear risk of one tactic being fundamentally far stronger than another.
If PF2 does only one thing, it is "there's no way to trivialize a fight". There's no cheese.
Yes, that means that just like level 4 players have no way to defeat a bear but to engage it in a "fair fight", level 20 characters have no overpowered imbalanced ways to not have to fight a level 20 beastie using the constraints of a "fair fight".
At level 20 facing a monster your own level is easier than it was at level 4, but that's just about it. Make it a level 22 creature and the math, the arena, the actions available, and the challenge will be comparable.
Why? Because if it was
incomparable there would be no way to ensure balance.
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Let's take an example. The
Scare to Death ability (feat). It allows you to spend a single action and quite literally scare a monster to death. By that I mean just that. It goes from full health to being dead in an instant. You spend only a single action to do this. This sounds like 3E-style gonzo right?
Yes.
And no.
That's because Paizo has carefully calibrated and restricted the ability in a way that is distinctly unlike the unlimited 3rd edition.
First off, it only works on critters your own level and lower (because Incapacitation). This is important, since it promises that GMs won't see their cool BBEGs go down to "trickery" (unless you start rolling only 1s on your dice of course)
Secondly, if you do the math, you end up with maybe a 20% success rate. 30% tops. If the monster has 300 hp, that means that your ability on average kills 60 or 80 hit points worth of monster.
But a regular attack does that too! If the regular attack does 50 damage but has a 25% shot at scoring a critical for 100 hp damage, the average does fall into the 60-80 range (62.5 to be exact). Note: this compares the feat to your first attack. Compared to your third attack, it is clearly better. But so is everything else.
So in that purely mathematical statistical sense the ability can be defended as "balanced". That's not what proponents of 3rd edition usually want. In 3E there are loads and loads of abilities that completely short-circuit the intended defenses of monsters.
Now, you might think this is the case here. If your initial Intimidation check scores a crit, the monster has to make a literal save or die Fortitude save, but will often fail on even rolling a 19. But that does not change the fact that you will not score that critical more than maybe 20-30% of the time.
That said, narratively the ability still comes off as jarring. Or "cool" depending on your POV. By POV I mean the game is clearly thinking of it being used in a regular dungeon fight where one quick monster death matters little. But in a more civilized campaign, let's say there's a gladiator arena. I find it hard to imagine gladiators wanting to go up against a hero with a proven track record of one-shotting his opponent (no matter their defenses) once every four bouts. You circle your opponent, the tension is rising... and then he lifts an eyebrow, and you drop dead from fright! (Another example of how singularly focused at standard dungeon delving Pathfinder 2 really is)
This should tell you if PF2 is a game for you.
If you consider this to put a lid on high-level heroics, and want build choices to make or break combats, stick with 3E (or PF1). If you consider this a huge boon, since now your high-level monsters are assured some measure of a "fair fight", and one group of min-maxed heroes aren't decisively more potent than another, at the cost of fundamentally restricting high-level game play to the same bounds as low-level game play, then PF2 is definitely the game for you.
Fundamentally, the only reason Scare to Death is restricted to level 15 is to offer more "high level hijinks". But the ability is still on a leash. It's not like 3E at all, where a careful combination of various abilities could shatter the math entirely. There is no balance-related reason the Scare to Death feat couldn't be offered at level 4, for example.
Z
Disclaimer: I have only GMd
one campaign from 1 to 20, so there can be more examples than this.