seriously, anyone who tells you that blockchain is the best way to solve a problem is probably on meth. you don't need a fucking blockchain for chatrooms, blogs, whatever.
Hell, in many use cases, even Activitypub could easily be replaced by RSS/ATOM;
to reference some ideas in the article:
> ATOM is easier to implement
> ATOM requires fewer resources
> ATOM can be produced/consumed by shell scripts or even text editors
 -- https://news.ycombinator.com/item?id=18013800