Those HTML 5 drafts shouldn't have had in the first place ANY specification of a particular video codec, open or closed source - that would be restrictive.
Requiring a baseline open source codec wouldn't be very restrictive, any more so than the way standards set other requirements for wide interoperability.
According to the vorbis and theora FAQs, vorbis is public domain and theora is BSD licensed. This is far from restrictive.