I don't think this argument, debate, what-have-you has any point, so I'm just gonna say my last piece and drown in the ratio:

The causes of suffering in this world are great and many and complicated, and the elimination of this suffering will require more than any single thing to achieve. This exercise gives us the bluntest possible instrument with which to solve as much as possible.

Eliminating capitalism would make the world a better place. But other evils would still exist, such as racism (despite the fact that capitalism created it, it will sustain itself without capitalism if we don't act to combat it). Other evils would still exist as well.

I read this question as what single thing would eliminate the most of the bad things. Capitalism would eliminate a lot of them, but is there a way to eliminate more of them? If the answer is yes, then capitalism is not the best solution, only a very good one.

Thinking on it more I think I'd say "I'd eliminate suffering." It's the only answer that would eliminate all suffering (my previous answer is just another trolley switch scenario that puts humans on the top track.)

This isnt a real-world scenario. It's a philosophical game, and the "correct" solution is going to be equally detached from material reality