what this affects
whenever you embed a Follow, Block, Like, or some other activity where the original id isn’t easily on hand, you can embed it as the object
without an id. in such a case, the shape of the activity becomes semantically significant.
for example, say you want to remove a follower. you typically do this with Reject Follow. but what do you do if you never stored the original Follow id? you embed it like so
1id: <some-activity>
2actor: <you>
3type: Reject
4object:
5 - type: Follow # this has no id
6 object: <someone>
now ideally you probably should be storing the ids for everything… but eh, what can ya do.