Have you seen this in person or just online? There’s probably more bad actors trying to push antisemitism ideas onto the left then there are real people in those spaces. Eventually, real people get tired of arguing with bots and paid shills and just leave the online space, leaving only the idiots.

The problem with using hippie’s as an example is that they aren’t a monolith and many hippie groups were just some flavor of cult with no real political ideology at the top other then being anti-establishment. It’s not surprising that many of them intermingle with neo-nazis, but hippies being left leaning is more a piece of fiction then history truth.