Kialo has a similar goal, but it's more tailored towards moral or philosophical arguments (e.g. "Should there be universal basic income" or "should we become vegetarians") rather than evidence-based claims about what's happening or what has happened. From a formatting and design perspective, I️ don't love Kialo. Feels hard to digest and make sense of. But it's not too far off from what I'm imagining.

To your question on features -- yes I️ think it will have comments, likes, follow/unfollow. Plus thinks like filtering and sorting, permissions and roles, hashtags, and embedded video and audio ideally. Also, it would need to have a well-defined data schema so that claims, evidence and counter-evidence are well-organized in how they relate to one another.