I can't believe I read through all that unrequested, "sponsored", collection of garbage features just to confirm that no, we still can't have the simplest thing that Slack, Discord - hell, even IRC (remember that? No? Was it before you were born or has social media corrupted your brain sufficiently that better means of communication have been erased from history?) had:
Persistent group chats (NOT Microsoft's ridiculous notion of "channels" which are styled after Facebook groups - cos they're so good, aren't they?) that are discoverable, or at least able to be linked to.
"Oh, ya, you just 'post a discussion' in a channel, and all your co-workers can hit reply ya" - no, you utter cretin, you don't. That's not how a conversation works. That's why nobody uses the channels anymore - because it doesn't work.
The last three companies I've worked with have essentially abandoned channels altogether in favour of endlessly newly spawned group chats which are subsequently named and renamed, the organisational mess of having to be invited in by an existing participant still proving to be a better experience than using Microsoft's idea of channels.
In the meantime, there's Slack (or Discord, or IRC), that lists all the organisation wide channels for you to join and join a NORMAL conversation without having to "post a discussion".
Whoever at Microsoft is in charge of ignoring this feature request - which has been outstanding now for literally years - needs a special award because of their sheer ability to block good ideas on the face of the overwhelming tsunami of common sense.
Just implement /list for chats - it's not hard.