you have just bring yourself into a negative approach here because imagine you directly told him to invest or
use bitcoin when the best thing to deal here is tell him to study and understand bitcoin and let him decide what
to do next , the money sitting in the bank is like funds that going nowhere but for bank owners favor.
your friends is good and smart enough to understand bitcoin specially if you will tell him your success here ,
but that will be the start of the journey.
Suggesting other people to continue investing without understanding Bitcoin of course this will be very risky and it is true that what you say will get us into trouble because maybe when they try it and fail on the first try of course they will blame the person who of course suggested investing. This will create a bad relationship with your friend. If you want to advise other people, I think you should explain in detail about investing, both about the good achievements and the losses you experienced while investing, so that when they decide to try it, they definitely do it with caution.