I do know some, maybe it's because I live in a university town. I think you were interested in today's far left, and those are the ones I've been frustrated with.

To a lesser amount, I also know one or two people who identify as communist. The best quote from them was, maybe if trump were to be president, then we would finally collapse the global economy so then every one would start over.

It does stem from a feeling that the current system is too broken to fix. They are valid feelings and I can only presume our lack of progress is because the Republicans have always had so much power paired with general concept that change is a slow process. But these people are tired of waiting and hoping for drastic change.