Having something already implemented is a good thing. It forces a minimal kernel, with progressive enhancement. If that's impossible to accomplish the next time, sure, create a new standard. But ideally NIPs are extremely easy to support, with lots of optional stuff.

> I don't think 7D can do BB boards and Slack/Discords at the same time.

I still think you're letting existing products dictate what we're building. It's ok to invent new content types. What exists is a very small cross-section of what makes sense, and in many ways the wrong one (which is why we're here in the first place).

> The discussions on a BB are not chats and are also not threads. They are almost like Mailing list discussions (heavier content/message), but not quite.

I'm not sure what you mean by threads here, but I basically agree. BB-type "threads" were what I was aiming at with 7D. My goal is to have a non-chat place within communities where more substantial conversation can happen, not a twitter-post-type thing. I really think your spec is the same thing, just more developed, and of course with markdown support. But unless tables or your specific way of organizing content are essential for forum posts (I don't think they are) I don't think there's any incompatibility.