In fact, I'd suggest even beyond that... just think about that claim. Love it or hate it or anything in between, wealth of all kinds has absolutely exploded under capitalism since the Industrial Revolution. If individual transactions in the world of capitalism are intrinsically exploitative and there is always a winner and a loser and a net loss of societal wealth... how can you explain the modern world, in which the poorest residents of the industrialized countries consider their birthright many things that the Kings of old could literally not have gotten at any price? Don't just read the propaganda, think. This is self-evidently a ludicrous claim if you take it seriously. It is absurd that the net effect of multiple trillions (quadrillions?) of net-loss transactions could somehow sum to something so net positive. Bridge the gap between theory and reality... don't just let people babble on and on about economics without ever asking them to be correct, think about what it would actually produce in the real world if it were true.

Capitalism has its problems. There may be better economic organizations. Capitalism may yet have a long term flaw in it as technology progresses (a lot of chatter about that case on HN in the past couple of years, there's a lot of interesting questions there). There's all sorts of avenues of "attack", or, better yet, all sorts of ways to just think about where we've been, where we are, and where we're going. However, it's a sort of basic "you must be at least this tall to ride the ride" sort of thing that your theories must be able to explain how wealth has exploded under capitalism, and why it didn't explode under the older systems, and why it doesn't explode even more under any of the several attempts to use another system that have been really tried in the real world. (i.e., don't try to claim that many of the obvious "fixes" to capitalism have never been tried when in fact they've all been tried numerous times, and so far have not generated the best track records. Theories should include and explain real-world data, not ignore it when it is convenient to do so.)

And should you be tempted to explain away the wealth, or claim with varying degrees of obfuscation that its distribution negates the wealth explosion entirely because it isn't to your exact tastes (an obviously absurd claim when spelled out clearly but a popular dodge when slathered over with enough words to mask the logic), I strongly recommend spending some time with 18th century medical case notes, or reading about the opulence of 16th century royalty with an eye to what simple things we have today that they would (quite literally) kill for, or something else that will simply rub in your face how unbelievably wealthy we are today compared to the past. The past is poor. You can have theories about how it could be better, but if your theories become so powerful they explain why the wealth explosion didn't happen at all, it's time to throw the theory away and find a better one.

(Incidentally, I do have ways I'd improve things myself. If you're reading this as a paean to the status quo and anyone criticizing it should just shut up, you've probably got a bad case of the propagandas rendering you unable to understand different ideas. I've got my criticisms. However, my criticisms and yours still need to take the all of the above facts into account.)