Cap is a Fighter/Battlemaster with military leadership abilities.
Widow is a Rogue/Assassin with military leadership abilities.
Hawkeye is a Ranger/Hunter with military leadership abilities.
Black Panther is a Monk/Way of the Panther with military leadership abilities.
So many heroes are a [enter class here] who can lead, inspire, and command tactically. Doesn't make them Warlords.
Captain America is a super soldier who was given serum to make him peak (or slightly better than) human capacity.
Black Widow and Winter Soldier had similar serum applied to them, again placing them above peak humanity levels.
Black Panther is enhanced by the special herb and wears an indestructible suit.
Hawkeye is the only member of the Avengers without special abilities, just trained to be a great archer and augmented with special arrow tech.
And everyone else has overt supernatural abilities, be they alien (Thor, Captain Marvel), radioactive (Hulk, Spiderman), tech (Iron Man) or magic (Dr Strange).
I bring this up because being a super soldier or using a special herb is still magic by another name. They aren't shooting energy beams or flying, but they aren't exactly normal. The closest you get to a D&D fighter is Hawkeye; a peak athlete with special weapons. And he ain't exactly trading blows with Thanos.
I bring this up because people want fighters to be mythical but not magical and I don't see how that is possible. It's fine to say you don't want them using spells and having spell slots, but I draw the line at "and he does it all nonmagically." NO. He does it all with some kind of magical origin. Now, I don't really care what that excuse is: all fighters could be super soldiers, all barbarians demigods, all rogues touch a magic herb. But that better be EXPLICIT in the write up that fighters, rogues etc ARE magically augmented somehow beyond the abilities of normal people.
And I don't have a problem with "every class in the game is magical in some way". All characters are special. D&D already feels pretty superhero. But I know there are people who want their cake and to eat it too; they want fighters doing fantastical things with mundane origins. They want Boromir doing Winter Soldier things. And to that I say "tough". Either fighters are mundane people who do not exceed what is possible in reality OR fighters are magical/supernatural people who can do fantastical things.