1. Marx agreed that capitalism is very good at rapid economic growth, which is why Lenin implemented the NEP and Deng Xiaoping implemented the liberal reforms. So why abandon that completely for the system like in Cuba or North Korea which are very inefficient and grow slowly?

2. Norway, Sweden, Iceland etc are the best places to live on earth. Clearly social democracy has provided the goods. Of course in recent years, due to neoliberalism, those countries are not as great places to live anymore, but they are still the best in the world. So why are you against social democracy if when implemented correctly, it is the best system we have seen? Communism also if not implemented correctly produced horrific results, its all about the implementation. Ideas alone are not enough.

3. The vast majority of workers do not want communism. How will you try to establish communism democratically when people dont want it? When people say they want socialism, they usually talk about social programs or nationalization of key industries, rather than implementing Cuba or North Korea economy, no one wants that.

EDIT : I have another question. Are communists willing to work with social-democrats? Obviously neoliberalism and fascism are bigger threats, so wouldnt it make sense to vote for and support social democrats like AOC in USA or Corbyn in UK or Mélenchon in France?