In Eastern Europe, Russia, China, Mongolia, North Korea, and Cuba, revolutionary communism created a life for the mass of people that was far better than the wretched existence they had endured under feudal lords, military bosses, foreign colonizers, and western capitalists. The end result was a dramatic improvement in living conditions for hundreds of millions of people on a scale never before or since witnessed in history. State socialism transformed desperately poor countries into modernized societies in which everyone had enough food, clothing, and shelter; where elderly people had secure pensions; and where all children (and many adults) went to school and no one was denied medical attention.

Michael Parenti, Blackshirts and Reds, 1997.

Improvement of living conditions in the USSR for example happened not just for a massive number of people, but at a pace not seen before.

In the USA, a prime example of capitalism gone wrong, there's poverty so bad that it's the 4th leading cause of death (and worse, the poverty may even be underreported). There's rolling back of social programs, overturning of child labor protections, destruction of the public education system, over-incarceration and for-profit slave labor-driven prison systems[^1]. Try to make me a similar list of government-backed initiatives in the USA that are intended to lift people out of poverty rather than put them there or keep them there. There's a lot of effort being spent on making sure people can't get themselves out of poverty. The USA is much more interested in punishing and continuing to exploit the impoverished than helping them--helping them isn't profitable.

Another thing you're conveniently overlooking is the destruction of the rest of the world, that is, the ones not being supposedly lifted up in those capitalist states. Even if everyone in the capitalist states was lifted out of poverty, if the cost of that was destruction of other country's economies and lives of the people therein, effectively putting them into or keeping them in poverty, then it's a wash at best. Capitalism is great at externalizing negative costs: externalizing it not just onto consumers, but onto citizens of the world, and, worse, onto the future stability of the planet and its ability to host life.

If you take into account the number of people forced into and kept in poverty worldwide and compare that to the number of people truly lifted out of and kept out of poverty due to capitalism, I don't think you'd be able to assert what you have.

[^1]: And if you'll remember, the only reason most of these social programs ever existed in a somewhat-useful manner in the first place was because the USA had to convince its populace that the existing capitalist system was better than the competing socialist/communist states it was waging economic and ideological war on. Once it was able to destroy the ideological competition, it could change its narrative as well: now, the failure of those socialist/communist states was due to inherent failures of the underlying ideology and not due to a concerted external effort to defeat it. Once there was no competition on the "treating-your-citizens-better-and-like-humans-deserving-of-empathy" front, tearing down of these programs sped up, and the money that was taken out of the taxpayer's pocket that should have funded those programs was not returned to the taxpayer but instead funneled cleanly upwards.