It would be hard to enforce such a mandate, especially considering the fact that the studios might not even have any idea of all of the episodes in a set are complete or not. A lot of times, edited episodes get released by mistake, because they were supplied with the wrong master for a...
The Fawlty Towers episode (at least) has been put back up on UKTV (since at least June 13th)...
from Chortle: ...with the Major's racist language intact (and a minimal disclaimer attached). On Virgin Media, no disclaimer is given, except the note that the episode is rated 12 for ‘language and...
Another thing that had the public at large buying DVD over blu-ray: being able to loan their discs out to "grandma" (or other family) who may only have a DVD player. They know that anybody they loan their disc to will be able to play it, but if they loan out a blu-ray, there's no way to know...