If they offered them "res publica" (to the larger public), then those would indeed be public relays.
Those would probably be the most-restrictive relays, tho, not the least-restrictive ones.
Discussion
Getting away from public relays was the entire point of building Nostr. đ€·ââïž Public relays _have_ to censor, as the people running them answer to the larger public and can't host anything the majority of the sovereign would find overly offensive.
The goal of Nostr is actually to have lots of different, easily-created and easily-maintained PRIVATE relays, where the person running it just answers to himself and any customers he might have, rather than needing to achieve some wider consensus.
Hi, Silberengel. Question from a layman :) : I just saved your post in my local computer, via a link from njump. Do posts on njump and the corresponding links have future durability, will they remain available for consultation? What guarantees this?
Every event you save to your computer is durable, for as long as you store it. Same as every event saved to anyone else's computer, including the one hosting the njump relay.
The best thing, is to have a local relay or database, hooked up to your client, and save a copy of everything you find interesting. Then you can always find the original, signed note, even if the internet link is eventually broken.
How do we currently determine whether the relays we use are private or public, and their respective restrictions, if any?
There is no way to definitively tell who owns a relay. They don't even have an associated npub; they're just websocket addresses, to the users.
The ones with whitelists and AUTH (community and/or paid) are self-explanatory.
The "public" ones also have restrictions, but they tend to obfuscate them. And they are prone to rate-limiting and throttling of particular npubs, rather than allowing/disallowing them outright.