And yet Vancian magic is scarcely found anywhere outside of D&D, particularly in video games. It is almost always one of the first things that gets discarded and replaced, typically by a mana point system.
Well, magic systems in computer games are fairly diverse, but there are still some that use quasi-Vancian systems for the same sorts of reasons Vancian works. Blizzard in particular has evolved to a sort of Vancian spell slot system for most of its games, differing only in that it has faster cool downs for your chosen spells - seconds rather than 'a game day'. The reason this works is enforced diversity. If you have slots on a cool down, well you are forced to use something else after you've spent a slot. That's one of the reasons I feel Vancian captures the feeling of old school fantasy so well, even settings that aren't Vancian (such as Middle Earth). Mana point systems tend to devolve down to one single trick that the player invests in and plays almost exclusively, which is fine and even works better for certain settings you may be trying to emulate, but is a tradeoff.
Mana point systems work in table top RPGs, but having played with both one doesn't work better than the other.
Since computer games handle book keeping well and typically have more combat and a faster pace of combat, mana point systems and particularly rapid recharging mana point systems work well for certain play styles that have nothing to do with table top RPGs. A video game like Path of Exile isn't in its gameplay concerned about creating an experience of being in a novel, because it has the visceral element of reflex play and immediate visual feedback as it's core aesthetic experience.
The point is that I have played a lot of different RPGs over the years (D6 Star Wars, CoC, Chill, Boot Hill, Gamma World, GURPS, Paranoia, Rifts, VtM, Exalted) and I've read the rules of tons more (I just got the Mousegaurd book for Christmas), and I no longer have this view of RPGs that there is this right way and this wrong way, or that there is this old way and this new better higher tech way. Heck, tons of the things that I thought were stupid advice in the old 1e AD&D DMG suddenly made sense when I found myself in Gygax's shoes running a game similar in many ways to the one he was running. Go ahead and try to run a game like Burning Wheel or FATE with 12 players and you'll see what I mean. (It's amazing how many indy games implicitly assume you have only 2-3 players ever, and code that assumption into the rules without realizing it.)
D&D's biggest advantage over most systems is that it evolved rather than was designed. The result was a kludgy mess in a lot of ways but by being evolved it did serve the gameplay it was designed to serve. The 1e AD&D DMG runs like it reads, and provides tons of examples of play that prove that. (Compare with the FATE book which doesn't run like it reads and provides tons of examples of play that prove that.) Compared to the book for Mousegaurd I just bought, that's pretty amazing because as good as the book reads, it's obvious to me after 30 years of running games that it doesn't run like it reads. (And to me watching a game like FATE being run is so entirely cringy because it is so obviously not creating the game it was intended to create.) For me, 3e is the near perfect system (granted, saying that, I admit I rewrote half the rules) because it serves that gameplay I was doing in the 80's in a more elegant way, letting me run my 1e AD&D game with the elegance that I wanted but couldn't manage back in the day.
Things I'm looking for in a system:
a) Players can make propositions with some expectation of the difficulty of the proposition and the likely consequences of failure. One consequence of this is that the adjustment of difficulty has to be fairly natural and granular, so that the GM also knows how he's effecting the odds.
b) Player have a linear experience of play, meaning that causes happen before consequences and decisions are made linearly in the same way you experience life or story.
c) DMs can enter into a just contract with the players where they are promising a fair game with fair rewards and deserved penalties. Good play isn't merely entertaining, wheedling, or conjoling the GM to be given breaks or rewards.
d) Players can become as immersed in the game as they like and the play encouraged by the game is natural "make believe". That is, as much as possible, good propositions in the play are the same as good propositions in a child's game of pretend and are phrased as much as possible exactly like that. Once the rules are understood, they should become invisible or at least transparent.
e) There is a certain amount of cinematic play where the dice create description, but not necessarily so much detail in resolution that the game slows down to a crawl.
f) As a player, the rules allow you to invest in a character with very meaningful connections between what you invested in and what you can do.
g) As a player, that there is a real risk of failure, but also the possibility of heroic success.
Systems I know I like: D6 Star Wars, 3e D&D and D20 generally, 2e Chill, classic Call of Cthulhu.
Systems I expect I would like: Pendragon, N.E.W.