It’s possible to view matrix rooms without an account, but it has to be supported by the server as it has to load the conversation history from other servers over federation before showing it. I’m not sure about how long this currently takes.
I think the key is whether it’s indexable by search engines and can be archived by archive.org. Any chat service fails miserable at this and is thus not acceptable for documentation.
It’s possible to view matrix rooms without an account, but it has to be supported by the server as it has to load the conversation history from other servers over federation before showing it. I’m not sure about how long this currently takes.
I think the key is whether it’s indexable by search engines and can be archived by archive.org. Any chat service fails miserable at this and is thus not acceptable for documentation.