What about a film that underwent severe cuts due to censorship upon its initial release? By your law, if the studio is able to restore the cuts and release the film uncensored, they would have to include the censored version too, since that's what appeared in theaters on its initial run. That would just cause too many headaches.

What if you've already released the original theatrical cut, then you have a director's cut you want to release? By your law, you'd have to include the theatrical cut with the director's cut, even if the theatrical cut had had a prior release.

The government doesn't need to be involved in everything. A law such as that would cause a lot more headaches than you seem to anticipate.

And a law requiring them to utilize the full capacity of the disc? That's stupid. That limits a lot of what you can do with extra features, commentaries, picture-in-picture commentaries, lossless audio mixes, etc. Plus, most films don't need the full capacity of the disc. Requiring them to use it is wasteful.