As someone reading this from the periphery (and not really even as I have been in the ecosystem, building etc), my first thought was this was some kind of live audio conversation thing ala Twitter Spaces. But nope. I know I know, you want to do your own thing, define your own naming, but alot of people still view things as far as Bluesky's relation to Twitter, in the consumer lens. You'll get there as far as independent separation but it's not there yet (similarly, Bluesky & atproto's connection/independence).
And this isn't even a consumer thing in this respect, but a dev/protocol thing.... couldn't have gone with something like Zones... Permissioned Zones?
Collins: "A particular kind of space is the area that is available for a particular activity or for putting a particular kind of thing in."
Cambridge: "an empty area that is available to be used"
why do you think Twitter called them spaces in the first place?
Isn't that exactly the problem?
It's like using "node" for something in your program's design, or "tree" or "type" whatever. Usually it's better to find a more specific name that communicates the intent even better, or at least less common name, as it'll inevitably will clash with something else, and by then you wish you'd name it differently than every other single thing out there. Unless it truly is only that thing which can be called "tree", don't suddenly call it "perennial" just because.