I think the “no easy way to respond to a reaction” is an important point. Maybe there should be a way to respond to a reaction!
I think in a very complete, robust social media system, reactions might just end up being very short comments that the site lays out in a more compact way (and if a flag is checked, omits immediate mention of the author and aggregates identical reacts with a number by default). The point would be that you could link directly to an interesting reaction, or reply to it, and if you reply to it it can be layed out as a comment the usual way.
I think in a very complete, robust social media system, reactions might just end up being very short comments that the site lays out in a more compact way (and if a flag is checked, omits immediate mention of the author and aggregates identical reacts with a number by default). The point would be that you could link directly to an interesting reaction, or reply to it, and if you reply to it it can be layed out as a comment the usual way.