Yes. Exactly.
But you don't have to like it...
Sure, but the problem is that retreating is an insanely varied state compared to just about anything else: it depends on the party's HP, resources, disposition, terrain, motives, and similar considerations for their foes... and I'm sure I'm probably giving the short shrift to other important factors as well. Even more than that, it's generally considered a
fail state, which means that the party is likely to be in trouble when it happens. Thus creating rules are difficult because not only is it sensitive to many different factors, but it is going to be in a disadvantageous situation for the players that could result in their deaths.
There is a certain element of, if it isnt on the character sheet or in the rule book, you cant do it in some circles. I believe in a little leniency in house ruling and GM empowerment to pave the way to smooth gaming. However, I also believe in discussing RAI and RAW when these issues come up and find GM fiat answers to be a bit Oberoni. Having these issues at your own table is one thing, but tournaments and organized play are stricter on GMs. Also, hopefully designers read these sort of conundrums and try and plan for it in future editions and new RPGs.
Oh wow, there is a community callback that I had to actually look up (though I know it under a simpler name).
And yeah, at a certain level having rules can help and empower players by giving them processes to hold the GM to. Combat is the most common example of this, though obviously PF2 has a decent amount of systems that the players can leverage.
Again, though, the problem with creating formalized retreat rules is that retreat is just such a varied fail-state that it's probably just better to proceed on a case-by-case. I mean, I'm going to suggest some rules at the end of this, but I would not want them to be more broadly-applied because I know there are some ways that they could be abused or not work.
Nope, I am. Once one side departs, the combat is over. What is gained by continuing to operate at a combat timescale with a combat action economy? Would you run exploration that way? Social challenges?
I think the problem is that people associate retreat with the combat, which is wrong: as was mentioned earlier, it's way closer to a "chase" scene than anything. But because it immediately follows/is involved with combat, people don't switch gears like that. People also fall into the "There is no tomorrow, only today" sorts of mindsets of destroying the enemy, rather than allowing contact to break off.
I vaguely remember seeing (and later having it pointed out to me) that there was a flight process in the context of dungeons, but as usual in OD&D (and for all I know, later) outdoors got short shrift when it came to addressing problems (noting the effort to split monsters into "levels" for dungeons, providing at least a crude encounter balance tool, while there's nothing really similar for outdoor encounters).
OD&D is so much closer to the proper wargaming roots than even 4E, so it makes sense to have retreat/fallback rules within the text themselves. As noted, though, they largely deal with being in a dungeon, so outdoor encounters don't really have the option. I suspect this was part of the start of such problems, along with the idea of the adversarial GM developing early in the D&D lifecycle.
I’d like to see Paizo take more advantage of the VP subsystem, since it provides a more general way of resolving these situations than the combat subsystem does.
This is not necessarily a bad way to do things, though I might riff on it a bit and say that you combine it with a 4E skill challenge. Be aware, these are very "Off the top of my head", early conceptualizing of a system, so they almost certainly have a lot of holes. But I'll put it out there.
To start, the difficulty of a retreat is set by the GM, dependent on a variety of factors, and translates to more or less checks to be made by each individual. So an easy escape would require 1 skill check, something a little more difficult would be 2 skill checks, and something very difficult might require 4 or 5 checks. But rather than needing a certain number of successes to get out, getting out is (somewhat) assured: the checks are to mitigate losses, rather than allow them to get away. This means that there isn't a huge fail-state some unlucky dice, but rather you're just more likely to be in a bad state once you get away if you do badly on the dice.
Players can choose what skills they potentially want to get away. DCs are set by the GM dependent on how appropriate they might be for the situation, and the players roll. On a success, they lose nothing. On a critical success, they can choose to give another success to themselves or another person in the party. On a failure, they'll choose something to lose. These losses, particularly modifiers on physical stats, won't immediately effect them (think adrenaline pumping getting them through most of this), but will come into play afterwards. A critical loss means the GM gets to pick what they lose.
Attacking can be used once, as a way of basically hard-breaking with the enemy. They can choose a spell or an attack and make it a DC check equal to their level or the most common AC of their foe, whichever is lower. This is not meant to be necessarily a damaging hit, but a show of skill in being able to disengage from combat. Non-combat spells can be used in conjunction to help amplify a skill, giving a bonus to a skill roll or lowering a DC with an appropriate effect (For example, an obscuring mist spell lowering the DC of a Stealth check.
If you want to use proximity as a factor, certain things (such as area effect spells, smoke bombs, etc) can assist the entire party if they are meant to be together. The party can also split up if they so choose, which can lower DCs if the party is retreating from only a few or a single individual (I would lower it -2 for a group of 4-7 foes, and -5 for 1-3 foes). This also comes with obvious complications of needing to find one another (unless the players discussed a rally point previously).
There is technically still the possibility of taking damage and being lowered to 0 HP. This can occur with a failed attack check, or as a cost for failing a check. If this lowers one to zero, the player may roll a stealth check. If they succeed, they either pass out in cover, or manage to crawl away into cover before their attacker can find them. If not, they are captured.
The costs of the checks are Mental, Physical, and Resources. Again, I'm making these up off the top of my head, so they aren't going to be the most detailed or the best, but I want to give a general idea of what I'm looking at.
Mental: These are mental afflictions that take time to wear off, often requiring a few days rest and a few successful Will rolls. Things like a Fatigued Condition until two days rest and a successful Will roll representing mental tiredness and being "off" after being forced to flee is an example. A similar Stupefied 1 state with a similar duration is another example for a similar condition.
Physical: Injuries from running away, coming in the form of levels of Drained, injuries which hamper skills such as Clumsy or Enfeebled representing pulling muscles or injuries endured in the escape revealing themselves when the adrenaline wears off.
Resources: This represents losing coin, tools, weapons, and other useful items that you were carrying. Perhaps the Barghest tore off your backpack when you weren't able to climb up the wall fast enough, or you managed to fumble and drop a potion you were going to. Perhaps the enemy managed to hit you with such force that your parrying blade ended up flying into a nearby ravine. As a rule, weapons and shields should be either damaged or lost (by both the party and the monster if it is so inclined), consumables destroyed or lessened in number, bags damaged and tools in need of repair or spilled out and in need of recovery.
All of these things should be done collaboratively with the player. They should choose what category and be given choices of what they want to take. If they want, they can spend 1 Hero Point per retreat to lose something small or the effect to be not as long. Ultimately these are meant to give some cost to retreating, but to avoid killing the players. Instead, they are given problems that they must now handle.