Breht and Alyson talk about this in their episode on Socialism: Utopian and Scientific when they talk about how Marxism is a science. Breht brought up some events that could falsify key pillars of Marxist thought (around 1:25 in)

• Anarcho-capitalism gets established
• If liberal democracy is able to resolve class conflict
• A non-Marxist left ideology is able to lead and defend a world revolution
• Fascism and imperialism is rooted out of liberal society

Any of these events happening would crush key views of Marxism.

Chinese-American. I was a Bernie soc dem and was kind of a self-hating Chinese second-generation immigrant because I heard from the media that I was supposed to hate China for their policies on Xinjiang, Tibet, and Hong Kong. Once I learned more about the CPC and read theory, I started seeing the world in a completely different way. Today, I proudly call myself a Marxist-Leninist.