The underlying ActivityPub endpoints use JSON-LD, which is much more HATEOAS than plain the JSON shown in the link above.
If you send an HTTP request with an header of 'Accept: application/activity+json' you get proper machine-readable data out.
Re:Every Mastodon User Has an RSS Feed
by CuriousSkeptic on Saturday June 24, 2023 @06:48PM
(#36463343)
Indeed much more applicable then, I stand corrected
Given the context I assumed the regular unspecified internal type of JSON commonly used to back SPAs
Your comment could just as well have said SGML or XML instead of JSON which would make the distinction more obvious.