Not sure how serious an answer you're looking for on the psychopathy thing, OP, but I would say psychopathy (or anti social personality disorder) doesn't need any hints.
Psychopathy is one of those overused words like "depressed" or "OCD" which we usually use outside of its psychological meaning, but it's an immediately obvious disorder. God love them, like, because it's probably deserving of being described as a mental illness instead of a personality disorder.
I've only met one person whom I am certain had this condition or a similar disorder. Quite a violent, extremely emotional person with no ability to regulate mood or maintain relationships. A total absence of self-deprecation was the least serious trait, but probably the most obvious: a mild ribbing would erupt into a ferocious tantrum. This person stole from their own parents, from friends, and caused one ex to have a nervous breakdown, through a mixture of emotional cruelty and, it is suspected, violence.
When it comes to your run-of-the-mill peculiarities, unusual traits or even quirks, I'd argue that the broad spectrum of human behaviour is part of what makes life interesting, and makes sustained friendships all the more valuable. I'd hate if we were all the same, life would be so boring.
One thing I am quite convinced about is that personality is fixed, and biological. You cannot change people. It's usually best (and better for the peace) to just accept people as they are. The vast majority of us are lucky to be situated somewhere in the acceptable middle-spectrum of traits, and sad to think, those at the extremes will probably never change. No matter what.
I think they can learn to cope with situations in manageable ways, but that's more managing their anger (or whatever) than eradicating it.
I guess the most frustrating thing is to see the terminology and “knowledge” of the condition (which I would not classify as an illness) shaped by popular media creations.
It’s a stigma you just can’t get away from.
And yes, incurable but it is possible to manage it if you are interested in getting it under control. Unfortunately this will depend on the severity as aspd, like all conditions, comes on a spectrum.