the picture is essentially claiming “communism, a supposedly purely hypothetical system of governing/economics has never done anything bad” which ok so? By the same logic it’s never done anything good either, because it’s allegedly never really been implemented. It’s comparing real life to ideals/fiction.

You're ALMOST getting it.

The point isn't that communism is great. It's that the communist threat that capitalist demagogues love to bandy about is purely hypothetical, unlike the very real and present harms of capitalism.