Nefermandias
Hero
Prior to 5E anyway, every edition has tried to codify the world outside the PCs. Remember the cloistered cleric? But generally I agree: D&D settings often try and identify important NPCs in the language of the PC options and I think that is a mistake overall. Either create different options, or don't stat the alchemist that sells tinctures on Brewery Street.
I would argue that NPCs following exactly the same PC rules is a 3Eism people just doesn't seem to let go.