The only way to “not understand” it is to be willfully blind. Their ideology isn’t the issue, it’s their tactics that align them with fascism.
Their tactics are absolutely Bolshevist. They mean to put people into gulags (Hillary called them “fun camps”) to ‘end racism’, ‘end white supremacy’, and end ‘unearned privilege’. NAZIism is not nearly as likely as a Commie takeover.