Their time preference is too high.

So, you could do what high time preference degen gamblers do. Perhaps show them something like options or perp swaps. But unlike degen gamblers, recommend a "safer" 3:1 leverage, ... for a small/tiny part of their holdings. They can go long or short.

Explain that this is risk. But they see gains and take some profits, and then use those funds for something fun, they might see bitcoin in a new light. Sure you could end up with a couple degen kids on your hands, so this is not actual advice. Just something to show them another way how bitcoin is used, other than buy and hodl.