The point is, that it is possible for someone who is technically savvy and who has a subscription to copy the streams right now. The reason they can't download

The point is, that it is possible for someone who is technically savvy and who has a subscription to copy the streams right now. The reason they can't download the entire catalogue is probably because netflix/hulu have(or at least I hope they do) a system in place which prevents a single subscriber from accessing streams at a speed above what would be reasonably necessary for watching things one movie at a time. Which means that downloading the entire catalogue would take as long as it would take to watch everything which is probably prohibitively too much time. However, if, say, there's a particular movie that is available on netflix/hulu which you want to distribute freely for whatever reason and you are technically savvy, no DRM(short of netflix/hulu controlling the actual hardware you're watching from) will prevent you from doing so. Therefore, DRM offers no additional protection beyond what a regular login cookie-based system with rate limiting would offer.