Sorry dude, but you made the claim. Do your own research. Or are you admitting that you are wrong and were totally just blowing smoke?
You made a claim. You provided a list of characters from myth whom you considered examples of 'mundane' fighter. Your claim. Your list.
It contains characters from myth who displayed superhuman abilities.
Cu Chulain, for instance, could throw three spears so quickly that all three were in the air at the same time.
Not super-human enough for you?
He could leap onto the last spear, balance on it, leap to the second, then the first, and ride it to the target.
Celtic mythology has heroes doing all sorts of bizarre, super-human, and impossible things like that. Killing with a shout, punching the top off a mountain, leaping over the walls of a fortress, etc. Blame it on the bards' use of hyperbole...
Roland, as already mentioned, performed some super-human feats in battle, not many of them attributable entirely to Durendal.
And, even though your list resorts to pulling historical as well as mythical figures, it's not hard to find some super-human feats attributed to some of them, as well. Yue-Fei, for instance, supposedly used a bow with a 400-lb pull.
That standard of realism that D&D strangely seems to resort to where the fighter's concerned is a very modern one.
Beowulf wasn't on my list either.
Beowulf didn't have any magical powers and wasn't of divine origin, so I don't see why you left him out. Except, perhaps, that the example of him ripping Grendel's arm off had already been brought up...
And I'm pretty sure I never read anywhere where Lancelot had the strength of ten men.
The "Strength of Ten" idiom was Galahad, and Lancelot and Galahad were both divinely-empowered, archetypes suitable to the Paladin more than the fighter.
You've just shifted the goal posts so fast I almost got whiplash. For the past several weeks, your whole point was that the 5e fighter can't do enough, and needs more to be on par with heroes from legend. And now you're saying that the 5e fighter is already doing inhuman things that heroes from myth and legend can do? Make up your mind, man.
"Not doing enough" does not preclude doing /something/, in fact it strongly implies it.
It's the fighter that's got an identity crisis going. On the one hand, the things it can do (beyond hitting stuff) in an active sense are profoundly constricted, ostensibly by realism. On the other, like all D&D characters, he eventually gets enough hps to survive absurd dangers, like falls from great heights, or going mano-y-mano with a T-Rex.
It's just another example of the odd double-standard D&D perpetuates.
I'm not up on my Asian or Celtic mythology, and I'm probably a little rusty on my Mythology in general, but none of the superhuman abilities you listed farther back seemed to come from any real myth or legend I recall. I don't recall too many legends of heroes who jump 20 feet vertically
Not that startling a feat in Celtic mythology, where the hero might leap over a fortress wall from a standing start.
, or can carry a horse on their back unencumbered.
sounds familiar, but I can't place it.
What do you mean a high-level fighter lacks superhuman levels of skill, strength, and endurance?
Well, there is a hard cap on stats, now. And bounded accuracy could easily be seen as creating the impression that improvement from level 1 is not all that dramatic in skills, in general.
Beowulf is likewise a just high level
And being high level lets you rip off monsters' arms, how, exactly?