Agreed. Though there are heavy SnS elements to settings like Greyhawk, when this work backwards, using a D&D system for a SnS setting, then the fit becomes incredibly awkward and cumbersome. This is one of the problems I have, for example, regarding using 5e or even Pathfinder for Primeval Thule. It seems that there are far better rule systems than D&D 5e for the sort of SnS world Primeval Thule wishes to evoke. I would probably consult Savage Worlds, Warhammer, PbtA/Blades in the Dark, and a few other systems first, including even Blue Rose AGE.
That said, it does seem weird to me that in the larger-than-life epic heroic fantasy of D&D, the martial capabilities and physical prowess of the fighter seem restricted to a greater degree than similar martial characters of the SnS genre. Or we may perhaps more appropriately say that the "fantasy" of the fighter does not grow in equal proportion to wizards. This is not strictly speaking a matter of mechanical Linear/Quadratic power, but of the class fantasy. As [MENTION=29398]Lanefan[/MENTION] posted earlier, the imagined fantasy essentially entails "take more hits" and "make more hits" as opposed to the wizard wielding cosmic powers of the universe. Magic items should probably not be regarded as a great "equalizer" given how magic-wielding characters likewise have access to magic items.
Incidentally, it seems as if Pathfinder 2 likewise views this as an issue that presents cognitive dissonance given how the capability of skills were stated as being expanded to permit fighters and rogues to perform more fantastical physical feats the combined skill tier and level system.