[tikhonj]

So it would change nothing. In which case, why have them copyrightable at all? If companies aren't going to take advantage of it anyhow, it seems additionally pointless.

Fundamentally, the main reason to copyright something is to restrict others' use of it. Letting companies restrict their APIs' use would be unfortunate, so if it there is really no effect either way they should not be copyrightable.