Hussar
Legend
Oh come on.In the DMG. Because Gygax was inspired by the literature, and the literature is full of magic swords (the vorpal sword is a sword because it's lifted directly from a poem. Lucerne Hammers don't go snicker-snack). But there was never any requirement to play that way. Gygax wrote the DMG as ideas and guidelines, not as rules that must be obeyed. Look at those early adventures. Oh look, a super-powerful trident (AKA a fishing implement). Look at the ones Gygax wrote himself. Oh look, a disintegrator rifle.
Let's play a little game. Let's go through those early adventures. For every non-sword magic weapon you can find, I'll find 5 magic swords and we'll see who runs out first.
Why is this even remotely contentious? Swords in D&D have dominated the game since day one. This isn't some bizarre revision of history. It's just exactly what was done.