history means nothing to the brain dead

Lenin, Stalin, Mao, Chavez, Castro etc...killed their own supporters when they took power. So the meme is def wrong. Once They get control they lock it down and subdue any and all opposition to their policies. Even the socialist who complain the leadership isnt...socialist enough or the way they think it should be. There are many different flavors of marxism and all fight each other when they get in power.

As opposed to capitalism which has famously never killed anyone.

Yeah the ratio is about a million to one

You’re not wrong.

Out of the list I'll give you Blair mountain. Famines and dictatorships, non-capitalist countries attacking others don't count. Evil people doing evil things, whether they live in a capitalist society or not, the economic system isn't to blame- the evil is.
The problem with socialism is that leadership in that system tends to attract evil because imposing the associated loss of freedom requires force which requires evil people. Your extensive list merely lumps together every grievance the left has with America.