Very true. Insane leftists refuse to believe objective, concrete, real evidence. Why else would they believe in the fairy tale of communism which goes against all of human nature?
Of course, the left refutes that there is even an objective reality and there is no truth.
Actually, speaking as a former leftist and *very* small scale student activist, its because they have examples of it working. Which they do - see the shockingly collectivist Israeli kibbutz settlements/farms. What they fail to realize is that communism only works in certain very limited circumstances and cannot work as a national system of government.
Communism only works and is not a monstrous abomination if and only if the following conditions are met, as best I can tell from history and personal experience:
1. There is a clear threat that needs to be dealt with or a goal that must be achieved that everyone in the group agrees upon. This is how lifeboats typically operate, or stranded survivors on a desert island work.
2. Literally everyone must agree to the goal and what they are going to do to achieve it. If anyone significantly disagrees with the broad strokes, it wont work.
3. The maximum number of people that can be subject to this is maybe 1000, often far less. Again, everyone must freely consent and agree with the goals.
4. Once the goal is achieved, either the commune is dissolved or a new goal is agreed on by all participants.
Fail to do any of these and it flies apart.