I think what @cryptocoin (and accounts) are doing can be valuable, but I'd prefer that to be a separate experience from comments.

E.g. there could be a new tab under each post called "Context" and folks could provide context links and notes there. So if I'm actually interested in context, I could easily find it (and in that case I would also pay sats to @cryptocoin for the value provided...). WDYT? It could even show up as a "context" box to the right of the post itself, to make it easily accessible and yet allow to have standalone comments experience.