You can't look at it like number of coins multiplied by current value. Market cap is an imaginary number anyway, but specially for cryptos. Consider this:
If I premine my own Pekicoin, and I have 10 billion coins on my laptop then I sell 1 coin for a dollar to my friend (so Pekicoin has 10 billion bucks market cap), that doesn't mean Pekicoin had 10 billion dollars flowing in. So there is simple no good way of accounting for actual money flowing into a crypto. (if someone knows a way, let me know) Maybe the buying of actual new coins would do such a thing, but that is hard to track.
So just because a shitload of Ripple have been premined that doesn't mean that it carries actual weight or importance among cryptos.
So in you hypothetical, 10 billion cap is not 10 billion coins traded at $1?
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