The protesters themselves tended to come from America’s upper-middle-class, displaying a feverous zeal that felt alarming. And there was no debate to be had about race and policing, opponents simply had to educate themselves.
During those decades of social change, the problem of Left-wing “moral relativism” was often a complaint of conservative commentators, but look today at the young protesters demanding that “Rhodes must fall” or “black trans lives matters”. They certainly aren’t moral relativists.
Relativism is a position you employ when you’re weak, to be abandoned when you win. On a wide range of issues, including race and gender, the Right has been more relativist for some time. Before the 1968 revolution those outside of power (the Left) argued for moral relativism, those in power (the Right) argued for moral absolutism. Now it is the opposite. Even things like claims to absolute truths (“trust the science”) have changed. Likewise with censorship, which is by definition a tool of the powerful.