I try my best to make my affiliation with crypto as private as possible(trading included), though it really depends to who I'm talking to. I don't wanna get my face hit by that $5 wrench, you know? I mostly say that I trade digital assets instead. Game currencies and such. People would likely think that I still act like a kid that still has heavy interest with online games, but whatever.
They start scheming or they think "I can do that, better than you" and I suspect they want to secretly start trading too.
If you told someone and they think that way, then fuck 'em. Ignore them and do your thing. Don't get too much negativity in your way.