The phrase I hear most that immediately tells me they know nothing about crypto (or much else relating to it for that matter) is “well it’s not based on anything”.
I’m at a point where I think it’s hilarious to hear it and I’ve started saying “I didn’t ask you to tell me you know nothing about crypto without telling me you know nothing about crypto”
I also hear “well those Russian hackers got paid in crypto so it must not be good”
Or “it’s all a scam” while there are plenty of scams out there, the core spirit of crypto most certainly is not a scam.
One time I asked an old guy about it and he proceeded to borderline freak out. Super insulting and explaining himself with ridiculous logic. I asked him if he thinks he knows more about the subject than the people with decades of experience and know-how who are developing it and adopting it? He said absolutely. I then asked him what his thoughts are of the internet back in the early days of development. He said he thought it was stupid and would never take off. The total void of self awareness this guys has blows my mind. Also, we were at an advanced electronics facility so he’s not unfamiliar with technology.
Anyway, it used to frustrate me, now it’s kind of funny.