I don't understand why a peer-to-peer network connection is different from Ajax. Browsers don't require user approval for 3rd-party XMLHttpRequest connections. WebSockets are even more permissive. Why is WebRTC being singled out here? If I were a conspiracy-minded person (I'm not), I'd have to wonder if this was some kind of corporate-driven attempt to suppress peer-to-peer networks. In fact, I do think this is being…
One of the key features of twitter, the global reach of hashtags, would be impossible. Twitter relies very heavily on being centralised. Anyone claiming to build a decentralised twitter needs a very careful numbers-based argument as to what the bandwidth consumption of being a popular user or hashtag might be.