For prepared spell casting.
We collectively moved away from the rigid Vancian spell-slots-hold-a-specific-spell-each-spontaneous-casting-is-a-specific-feature because it's frustratingly tedious. Preparing spells is enough of a pain in the ass, but if you're gonna make me choose each level of each spell each day, I'm just gonna invest heavily in wands and scrolls, because I don't like these arbitrary limits and you've provided me with a way around them.
And sadly, as muchly refined as the specific combat balance of PF2e is compared to 5e,
The balance is in the exact same place as in D&D5e - action economy, resources-per-day, and increasing proficiency-vs-dc across levels - PF2e just actually fundamentally implemented those ideas, rather than 5e carrying its grognard baggage.
Look, when PF2e says that dual-classing - being two whole classes but with the highest of either class's proficiencies/hp/etc (in D&D, referred to as Gestalting, almost universally considered for epic level 'we're playing gods' games and otherwise broken AF and not even a real or considered rule) - isn't really an issue for combat balance at all in PF2e (none of the multiclass methods are, of which there are 3, save for a specific instance that becomes available, which the text warns you to watch out for, instead of assuming you can't balance your own game and doing it for you ala 5e), it just makes a character more versatile and somewhat less death-prone - You know PF2e has their balance shit locked down tighter than 5e's whaaaaaa-shitty-D&D2e-style-multiclassing-and-magic-items-break-the-fucking-game.
It's not perfect, there's still enormous room for human error in tactics or expected impact in combat, but it's WAY better than the nightmare of 5e...
as focused on the three-point-action economy as PF2e is, wholesale replacing spell slots with points ala 5e's attempted variant is (much like 5e's attempted variant) really gamebreaking.
Which is sad, b/c spellcasting is a HUGE part of these kinds of games, and PF2e does so much better at literally everything else 5e does, it's become my go-to thing whenever I gripe about how things work in 5e:
"Does PF2e do this? Does PF2e do this better?"
Aside from spontaneous spellcasting, the answer has been unequivocally, 'Yes, yes it does.' It's stopped me trying to 'fix' 5e, knowing that in most cases, how I'd try to fix it is how it's fixed in PF2e anyway.
