It all boils down to this:
How much knowledge do you need?
If you can explain to someone how to send and receive a Bitcoin transaction, then they already know as much as they do about fiat. That gets us about halfway there. Then you have to explain security, backups and personal responsibility, which might take a bit longer. Emphasise the part about how there's no one who can intervene to cancel or refund a transaction for them and you're pretty much done.
How is any of that difficult to explain?
Agreed. It is similar to saying that people should be careful on taking loans from banks because the fractional banking system takes more than 1 hour to explain.
However, people should be careful taking loans from banks because of the fractional banking system heheheeh.