We don’t know because its never shown, but Luke flies a Skyhopper, some kind of stunt-ship and “bulls-eyes womprats… no bigger than two meters.” In the later lore its explained this is some kind of suborbital craft and his flying around beggar’s canyon is pretty impressive, much more than “pod-racing” that’s for sure. Blowing up targets that don’t shoot back is probably the extent of his training. He grabs a rifle pretty fast when going to look at Tusken raiders, but gets ambushed before he attempts to get a shot off.
Luke was interested in joining the academy. For all we know he might have used simulators or taken lessons with Biggs, but that’s speculative. Episode I dilutes that in our minds by saying “not such a bad pilot” could refer to anything, including flying a glorified hovercraft soap box derby on the surface (albeit a really dangerous one).
In the novels (released before the movies, and based upon early script drafts), Luke gets more training than we see onscreen, but not much more. Years pass between episodes, which is not the case with the sequel trilogy.
Sure, Rey could learn about ships (she certainly has an interest, with her daydreams) by salvaging parts, but it seems even more of a stretch that she’s so good, than Luke. So whatever one says about the plausibility of Luke or Anakin, it goes double or triple for Rey.
In the end, the movies leave us with the distinct impression that Rey’s abilities are magical, from her learning to knowledge, even to her skill, not just force potential.
Had we always “known” that proficiency was passed on simply by touching objects or being related to someone, it would be a lot easier for fans to swallow, regardless of the comparative qualities of the movies they appear in.
By the time of Rise of Skywalker, it appears that video game/RPG rules are in place. Once you reach this particular character level, you unlock X and Y powers. Get stronger and you just know them, because you have enough experience points. In universe I guess the Force “wants” you to have this power or “knows” you need it and so you suddenly have it. Yet we see Rey getting new powers but not Kylo (I guess you could say he “learns” force heal after Rey dies after she “healed” him… I guess giving him her powers at that point, but they’re a dyad so maybe they always had the power in them, they just had to believe in themselves).
Was Anakin “good with machines” because of the Force, or was he just a prodigy, or was it just taught to him in his life as a slave?
In Force Awakens, Rey gets her powers boosted by Luke’s lightsaber (which calls to her and touching it gives her memories and even skill). Touching Kylo Ren’s mind gives her access to all of his powers, apparently. Maybe she gets knowledge of how to use the Falcon (never implied in the movie but I’m running with it) by touching it.
It’s not just Rey and Finn who are OP, look at Poe Dameron. Or the Emperor in Rise of Skywalker. So its an overall issue, not just the one character. Kylo Ren goes back and forth between being embarrassingly bad to OP. I guess something about the “force dyad” struggling for control between them? Rey gets stronger as he gets weaker and so on? The Sequel Trilogy seems to be doing its own thing (much like the Prequels did their own thing). It’s just the passage of time and different creative minds behind it (while mimicking the style of the earlier films) that makes it jarring to so many, even leaving aside whether you liked the movies themselves.
IF you start from the standpoint that all Star Wars is “canon” and “has to fit together” then I guess you’ll always accept it and reinterpret the old stuff in light of the new. So maybe Luke touching the lightsaber in Ben’s hut gave him Anakin’s skill too, and maybe getting into an X-Wing gave him the skills of the previous pilot who used it (Anakin’s pod was rebuilt from used parts, according to the novelization). See? And if you have a problem just say “a wizard did it” I mean “It was the Will of the Force.” 😉
Not saying I agree with it, just that’s how you could do it. I am of the mind that Disney Star Wars just isn’t canon. It’s like infinites for me.
Whatever flaws or conveniences were true of the Originals and got worse in the Prequels have reached an even greater height in the new stuff, and that’s no surprise because the new ones are consciously trying to copy (rather than expand or improve) upon the earlier ones, with, if you ask cynical, jaded (but I reject terms like “toxic” or “hater”) fans like me, rather mixed results.