Have you ever used Debian? It already doesn't distribute many codecs for precisely this reason.
(Oh, and I do use Debian, five days a week, but I don't see how that's relevant to my question.)
It is a version of Firefox with the branding removed as that portion has a copyright by Mozilla. This project started in 2004-2005.
I actually thought the policy in the original post has always been Debian's policy.
You can taint your install with pretty much anything.
I have access to more firmwares blobs than with Ubuntu.