I like what you said toward the end around conversations and misconceptions on internet/social media. I think you're right - social media can be a terrible platform for serious conversation. But, I also think that there are ways it can work despite this - people have serious debates online all the time, even if it is sometimes misguided in approach. There are articles that talk about important topics, people who raise important issues on social media that sometimes catch the eye of the public at large. Heck, the march for sciences protests in the US were organized via Facebook groups.
I don't think we are re-learning the rules for civilized conversation so much as we are re-writing and re-discovering them in the context of new mediums of communication (though I guess they're fairly similar). I believe the ability and willingness of people to participate in meaningful conversation really comes down to two main factors: how they personally view interactions with others and how the system incentivizes them to interact. You need both to really be able to have these serious conversations - without intention the person will eventually choose to discontinue and without incentive from the platform people may feel disenfranchised from continuing even if they want to. So, if you can facilitate a platform that allows for both of those to happen, you can possibly facilitate serious meaningful debate.
Sorry, guess this got a little rambly ;0) Hope it at least makes some sense though. I tried to make it so it wasn't too unfocused.
RE: Stream of Consciousness and Social Networking