Inventing Warp drive is an intelligence test that all space faring cultures must pass before they are welcomed onto the Galactic stage... Or more honestly, it's the point from after which their idiocy and barbarism can no longer be ignored or confined to their home system.
You don't remember Archer constantly bitching about how the Vulcans had had Warp 8 ships since they came to Earth a hundred years earlier and that the Vulcans were utter assholes for denying his father their magic warp 8 secrets as he went insane from envy( No seriously. Mental illness, and bigoted rants. It's all there.), when his magnificent Enterprise was only a warp 5 vessel on paper, and could barely make warp 4 on a good day?