What if all entries in threads backlinked to other threads they were in? Or threads themselves backlinked to if they were posted in other threads? It would be possible to weave fairly complicated structures here. But, it might
What if a thread creator could set rules for what replies are valid in a thread? Cloudflare Workers has a great streaming HTML parser, so we could fetch submitted links and parse them for different stuff. Like imagine accepting only websites who's background color is green, or, more seriously, only websites that link back to the thread itself, or other entries in the thread.
You could also have rules based on the URLs themselves, only allowing links from Wikipedia, or blocking all large social sites.
What if people could annotate entries in a thread, and then the thread creator could moderate them in someway, both positively, highlighting things, and negatively, removing things that aren't contributing to the conversation.