Elans do this too. Yeah, a warforged would have a distinct survival advantage, but it’s also pretty important to point out that warforged aren’t a race. They don’t breed and they don’t compete for resources with real races.
If you are speaking of actual gameplay instead of setting versimilitude, the warforged survival advantage exists at low levels only. After that, the survival game rapidly breaks down.
I’d allow a few alien robots and whatnot, but it would be a one off thing, a kind of whacky sidetrek. A warforged would be a unique character. A drow elf would just be a mutant elf with none of the baggage from other settings (and probably make it adapted to the sun as well).