We can do a present day apples-to-apples comparison: how does the life of a North Korean scientist compare to that of their Southern counterpart? I think the latter is probably better off overall.
"Capitalism" and "communism" aren't operating systems that get installed on different countries but impose identical function. South Korea has a much more planned and centralized capitalism than the Anglosphere. North Korea is basically a monarchist personality cult rather than anything resembling the Soviet Union.
That's not apples-to-apples, because clearly in today's world capitalism is more favored and has much more resources (taken by force). Not trying to argue whether one is better than the other, it's just that the current state of the world has a major bias for capitalism and against communism due to sheer quantity of people/power. Although I suppose that strength is a result of the differences between the two ideologies. I think it's mainly the result of the outcome of WW2 though, but that could be due to the differences as well! Maybe if they each had their own planets where they didn't have to fight we could find out...
Maybe the point that you are making is that communism is worse because if capitalism can also exist, it will take more resources and make communism miserable. Or, that if communism were widespread that life would be more miserable for everybody because we wouldn't have the capitalistic systems to make life more luxurious. Anyways, there's been plenty of debate on this topic, I just don't think there is any way to make a fair comparison in today's world. Even though these countries have similar ethnic makeup and size, I'd still say it's more of an apples-to-oranges comparison.