I STRONGLY suspect that there is a enormous gulf between finding out things on your own and being directed to them by a peer.

When you find something on your own (existential risk, cryonics, whatever), you get to bask in your own fortuitousness, and congratulate yourself on being smart enough to understand it's value. You get a boost in (perceived) status, because not only do you know more than you did before, you know things other people don't know.

But when someone else has to direct you to it, it's much less positive. When you tell someone about existential risk or cryonics or whatever, the subtext is "look, you're weren't able to figure this out by yourself, let me help you". No matter how nicely you phrase it, there's going to be resistance because it comes with a drop in status - which they can avoid by not accepting whatever you're selling. It actually might be WORSE with smart people who believe that they have most things "figured out".