Part of the difficulty of bringing this about is making p2p easy for users. I have high hopes that WebRTC data channels can start tearing these walls down by making it as simple as opening a web app.
As a general concept, P2P is easy for users - using bittorrent clients, TPB, etc. is essentially mainstream.
The one thing that would be nice is browser support - I would love it if Chrome had the option to download .torrent files using the Chrome download manager.
Thanks to web seeds[0], this would allow providers to convert any download to a torrent instead, both increasing use of P2P and decreasing their own server load.
Users wouldn't even need to know that they're using Bittorrent to download files - all they'd see are faster download speeds.
I wish that were true, but I am forced to disagree; it's been my experience (and that of my tech-savvy friends with whom I have discussed this UX shortcoming) that most people don't know how to torrent (much less set up and use freenet). Showing my parents or most of my siblings how to use a torrent client in conjunction with a tracker site is not going to be a fruitful task. If it's not as easy as Youtube or Netflix (click and watch), they aren't going to put in the effort to learn or remember how to do it.