It's not completely clear to me how various zones of the Fediverse distinguish "scraping" from "non-Mastodon ActivityPub services functioning according to spec in ways I didn't expect."
Given how frequently protocol behaviors act as ethical markers ("if you *can* do it, it's fine") this seems like a fruitful territory to try to map…
(I say this as someone who has myself been surprised more than once by AP implementations that put Fedi posts into unfamiliar-to-me contexts, don't eat me.)