I think there's no proof that Bitcoin has zero value, how can be a great coin become have no value if many people are still want to buy this coin
If no one wants to
The OP didn't really make that distinction from the start. Now that the issue is intrinsic value, I'd agree. Bitcoin has no intrinsic value. Satoshi himself made that point in his early postings. What the market uses as money never boils down to its intrinsic value.
Whether it has value is another matter entirely. That determination is up to the market.
It appears the OP will never get it. Therefore, we will never have the time to explain it to him.
I suppose we all can try though. 