It's gold-like, which seems congruent to me. Yellow by itself doesn't say too much about capitalism, maybe anarcho-capitalism, but not capitalism as a whole.
What I think is that the symbol has to be credible, it has to make you think "Yes, this could definitely be the symbol of capitalism if they didn't feel the slightest hint of shame".
That's why I think this is perfect as it is. I see it clearly being posted on 4chan by an anon presenting it as a symbol of the capital of kekistan or some shit like that.