" There will only ever be 21 million. You can send it anywhere in the world in seconds, and the reciever has final delivery and posession. We aren't going to find a giant deposit of bitcoin in Africa or on an asteroid. Elon Musk and Robert Kyocera both have significant holdings. Boomers aren't interested in it because they won't live long enough to witness its potential. Boomers aren't in the habit of planting trees for their great grandchildren.

All you can do in an elevator is whet their appetite, not dive into philosophical debates. If they want more information you can talk about what money is in the hallway, then send them to SN.