Not really. You could enforce that as an option on certain threads but you could simply have it be open with a single switch

I tried it out and it was a weird Slack alternative that was just that little bit of clunky where you couldn't use it on a daily basis. I actually feel some of the ideas were sound. I wouldn't have minded a thread-only topic where people post a bug at the top and discuss that particular bug below. It's hard to explain but there was just something about navigating all of it that made it just slightly more painful than was bearable. I'm sad to see it go because it could have made for a decent alternative to slack but it's so dumb that it shuts down so soon

So it was basically a message board?

Uhm, isn't it still true for Slack? Every message to the channel itself is kinda a thread.