I have a friend whose background is a lifelong membership in what used to be the "left". Her family was big in the politics of labour laws, our national health system, workers' rights – that was the "left" to her and that generational sector and it still is. I have another friend who was an activist in the anti-Vietnam-War movement in the late 60s and to him that is the "left" and still is. It is difficult for him not to identify the Antifa/BLM "protests" with his own youthful activism; to him police brutality is still what it was in 1969 in Pittsburg so Antifa/BLM are maybe too extreme but still basically the Good Guys.
This type of person just has no way to understand what has become of the "left" – or perhaps better, what has co-opted the left. They have great difficulty taking the academic leftists seriously and they don't get the connection from "Gender Studies" and "Black Studies" to campus repression and intimidation and, still less, to the insidious infiltration of this new fanaticism into all our bureaucracies and every level of education right down to elementary school.
They are all rationalists, secularists. We all were. My parents were Great Depression tweens and World War Two young adults and that was the most rationalist, irreligious generation in history, or so I do believe. George Orwell thought the same. They and the culture they made and that still stands today cannot process the religious fanaticism that has taken the label of Left. I am lucky enough to have a foot in both camps, having been acquainted with the Hippy era and having had to deal with and protect my loved ones from the dark and criminal side of it. So I can see things that many people my age can't. I was lucky enough to have met and befriended a former Vietnam veteran and mercenary and then to have met and befriended a former, recovering, South American fascist.
George Orwell wrote a passage to the effect that his generation were seeing the resurrection of characters thought to be dead for centuries. The Grand Inquisitor and the Witch Finder General had sprung up unanticipated out of the very soil of rationalism. Most people my age or even my kids' age don't get that the extreme Left (now becoming the only Left) and the extreme Right are the same thing, joined in a deadly triangle by the Secret Societies, the self-labelled Intelligence Agencies above them both, and that they are religious true believers, fanatics.
That's beyond their comprehension. They've never met a recovering fanatic who ran death squads when I was in high school. I have.