Actually from the two you listed above, there is no minformation in them. If they are told that bitcoin is volatile, of a truth, bitcoin is volatile there is no doubt about that. The other opinion is that bitcoin can rake someone.
This is truth because when you don't monitor your portfolio and enter the market at the wrong time your portfolio can go to zero.

So, there's no minformation, it is truth told in wrong way. When you meet such situations, don't try to debate in favour of bitcoin. But tell them the truth as it is supposed to be and allow them make their decisions.