Ultras miss one of the foundational aspects of Marxism in that completely derails their entire perspective and analysis.
Socialist countries and their various leaders were ALL EXPERIMENTS.
Missing this view in turn impacts why ultras are so hostile to the LGBT and hold the views that freagle outlined.
One of the major things that sets us apart from fascists and liberals is that we do not have an idealized, cultish, worship of the past and our leaders. They all made mistakes, they all had misinterpretations, they were all human, and they were falliable.
It is from this that me must not dogmatically cling to the exacts same views and Stalin, Castro, or Lenin, but instead take the successes of their experiments and build upon them while rectifying their mistakes.
We must flow like water and adapt to changing times. Never ceasing to learn, grow, change perspective, or improve. Ultras refuse to do this and that is their downfall, because the material and social conditions that created past countries and leaders will never be replicated one for one, which is why we must forge our own paths, and build on the knowledge of those that came before.
This is why the modern left movement has embraced sexual minorities, something that had not been done by previous movements, and thus, hated by Ultras.