What's stopping a re-examination of historical cover-ups? I think you answer your own question when you say: where's a good place to discuss this without going into conspiracy spirals? I mean that any time topics like this come up, people who are sincerely interested have to constantly militate against the "conspiracy theory" stigma. If you're hit with that label, you're persona non grata in academia, news media, and mainstream accounts on social media. That's what stops people. The places to discuss conspiracy adjacent topics would be alternative platforms like this, until news media slowly come around on accepting anomalies many years after the fact: Jack Ruby did have mob ties; the Saudis did seem to fund hijackers, etc.