Yes, ethereum developers right in the whitepaper and in early articles discussed methods of allowing 'light nodes' to exist. It's very important, actually. A node can even store recent data, as well as propagate new blocks, without keeping the whole chain, and this boosts the resilience of the network.

In my opinion, in the future, people will look back at copyright and see it how I also see it: a scam. Attribution is the only value in a zero cost to copy system of media distribution.

It also heralds a switch from this broadcast, centralisation of media distribution towards various scales of performance becoming more socially important. It's already happening. Bands are starting to issue their own, often free recordings, as a way to pull more punters into their gigs.

Artists make the most from gigs, and the more they can organise them as well, the better. So the marketing being cheap works in their favour! Make the fans, the marketing department. It's not like they aren't already.

Sooner or later, people are going to realise that we don't need big brother to make our fans pay us. In fact, by doing this, we limit our fanbase.