Yes, you are right, communism doesn't work. We are not talking about communism. That is what YOU want to talk about, because it is much easier to make an argument using extremes as examples than to consider all of the nuances. There is not a snowball's chance in hell that the US would ever be like Cuba or North Korea or the DEFUNCT USSR, but those are the boogeymen that fear mongers find most readily accessible.
The debate about what is "socialism" is not settled. Technically it has historically meant private ownership of the means of production, but that meaning is only relevant since Marx, and it has had many different versions. Countries as in Scandanavia like to call themselves "socially democratic" rather than "democratic socialist", but there is debate about the real difference in these two terms. When youth, the point of this article, and others like Sanders, talk about socialism, they are referring to "democratic socialism", but as they point to the Scandanavian countries as examples, there should be no doubt about their definition.
You, on the other hand, want to talk about "true socialism", of which there is no such thing. There is YOUR version, which is Cuba and North Korea. YOU can talk about that, but that is not what everyone else is talking about.
So you want to point to China? OK, it is officially a communist country, since the Communist Party is in control. But it has adopted substantial capitalist systems, while it still employs central planning, but it is considered a socialist market economy. OK, so you explain Busler's argument that socialist systems stagnate, using China as an example.
Thanks for the debate. It was fun.