This is a great exercise. When I was on the job market, we worked a lot on our elevator pitches, to explain our dissertations very briefly. We'd practice 2 min, 3 min, 5 min versions and target them at different audiences.

It's hard to do this on the fly with a complex topic, especially when the salient points vary by who's listening.

For that situation something like "Yes, it is similar to those, but bitcoin doesn't lose value over time like your dollars do." might have been the way to go. If you don't know that people care about the more ideological benefits of bitcoin, just stick to the benefits to the user.