"Pure capitalism is so cruel at times that it cycles rebellion"

That just seems like a blatant falsehood to me. In capitalist societies, expectations tend to rise and expectations can be more complicated, so there may be for disappointment or indignation, but I'd like to see a factual backup of that statement. Where have capitalist societies been objectively more cruel than any alternative? And where do you see more rebellion in capitalist countries versus non-capitalist? Has there been an uprising in Singapore or Hong Kong that I haven't heard about? Is the destitute condition of much of Africa the sad result of well-defended rights to property & self-determination?