Why is that "nasty"? Why even debate or get so defensive about this point?
For very strong reasons it does absolutely seem that the creator of Bitcoins did an early and heavy accumulation of the currency. The fact that they didn't "cash out" (which is rather irrelevant to whether it is "wealth" or not, as an aside) doesn't justify their mining, but actually makes it significantly more questionable -- they added no liquidity, instead actually restricting liquidity by doing a land grab of the easily mined coins. That is not altruistic.
Having a single, mystery figure holding a substantial quantity of a currency is absolutely worthy of debate.
Personally I think Bitcoin will be a v0.1 to something similar in the future. But I do absolutely believe it is effectively a pyramid scheme right now, and the rise in the currency is a combination of limited liquidity coupled with mainstream news and a gold rush mentality.