This comment for example, after about a week or two most of the visibility and interaction of it will drop to zero. At that point, this comment should expire and no longer exist.

That’s an incredible naive and egoistic take. Think about all the knowledge that is getting lost by applying this approach. How many times have you searched for some obscure thing and found the answer only on some five years old reddit post? That information would be lost for ever if you had your way.

That’s the wrong comment.

And to use it with a similar feature set, everyone is using different extensions which also have to be supported by the clients. I know there is this one server implementation (name escapes me at the moment) and Conversations on the client side, but it’s hardly the standard and we’re not really talking about plain XMPP then anymore.

Nobody is talking about Diaspora anymore ¯\_ (ツ) _/¯

If you think search engine giants like Google can’t track you when you’re not logged in, you think wrong.

There have already been projects like that in the cryptocurrency space.