I can see your point; it's not an uncommon concept in fantasy literature or contemporary RPGs to feature protagonists who're more powerful -- some of them even legendary (such as many manga books, for example).
It's interesting to follow manga back, actually: modern fight manga derives a lot from kung fu movies, which are themselves derived from kung fu novels, which themselves follow on from classics like Journey to the West, Romance of the Three Kingdoms and Outlaws of the Marsh, which themselves borrow a lot from oral traditions. Humility is a big virtue in many of those stories, as it is over here, but it's often applied to attitude but not to power.
And therefore I'm not claiming computer or video games are the only influence which has "conditioned" people towards "instant gratification"; I do, however, believe that they're the biggest reason why some people are reluctant to play if you must start as a dirt-poor farmer's son taking his first steps on the road towards heroism.
I don't know if it's so much that computer and video games are the reason, mostly because it's hard to say how much is the influence of one thing and how much is the lack of influence of another. In the early 80s or so, dirt-poor farmer's sons were the dominant RPG paradigm. Even Champions and the like would start out awfully tender in point value compared to what you saw in the comics. Gradually, though, you started seeing more games where you started out closer to what you'd eventually end up as, such as the WoD games.
It's very hard to actually tell, of course. But I can't help but wonder just how much of the shift is due to outside influences gaining dominance, and how much is due to the "start lowly, end heroically" play style just not having the same sort of first-to-the-market, duplicated-by-all status it used to. I suspect it's a mix of the two and of other factors I may not be tracking, but it's damn hard to tell.
And, in fantasy literature I also prefer the bildungsroman in which the protagonist(s) grow to become hero(es) as the story slowly progresses (BTW, even if myths feature superhuman protagonists, they're often flawed and tragic characters with ultimate weaknesses; something which D&D doesn't handle well).
Well, technically one would hope that the protagonists who start humble and those who don't
all have sufficient flaws and weaknesses to make them interesting. But I quite sympathize. I tend to be more eclectic in my preferences, but I'd be unhappy if I didn't have the Prydain Chronicles and Lord of the Rings to sit alongside my copies of Romance of the Three Kingdoms, Jonathan Strange & Mr. Norrell, and Orlando Furioso. I enjoy a humble protagonist as much as anyone.
While it may be true that it's more uncommon to have "farmer's-son-fulfilling-his-destiny" than a mythically powerful character as a protagonist in fantasy, many well-known series (e.g. LoTR, Eragon, and Wheel of Time) *do* portray "1st level" heroes as well (although undeniably exceptional and "destined-for-greatness"). However, except for Howard's stories (Kull and Conan), I cannot think of a mythically-powerful protagonist who wasn't a tragic figure ultimately brought down by his/her own hubris, flaw or betrayal (Elric, Achilles, Beowulf and so on).
I wouldn't call Beowulf brought down by flaws or hubris; "betrayal" maybe, but he fought the dragon out of duty and bravery, really. To Howard's figures I'd add Ruggiero, Bradamante, Orlando and Astolfo from the Italian romances, Sun Wukong and assorted company from Journey to the West. The real question is "is this a story where we get the 'happily ever after', or is it a tragedy?" Power level may or may not attach to that; the Orlando romances have happy endings, Arthurian stories don't. Journey to the West ends with everyone becoming Buddhas and Outlaws of the Marsh ends with the heroic bandits mostly slaughtered. LotR and Prydain end with the decided mixed blessing of magic leaving the world. D&D tends to try for happy endings,
As I said, I can understand your point about being able to jump into the game -- this may be natural evolution for games in the contemporary society. However, I don't personally find it to be satisfactory or fun to be able to play Kratos or Samson or Thor right from the start. Different strokes and all, I guess.
That's what it all comes down to. I just tend to suspect that the desire to start stronger isn't a new thing. I also wonder if it isn't partly because the start-low-end-high model was "unusually" strong during the nascent days of RPGs because that's what the biggest and first-to-market game was doing. But like I say, it's all theoretical.
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