If Dollar dies, everything dies. Simple as that.
Simple Logic: If bitcoin was better than Dollars, why does everyone freak out when we see a crash? If bitcoin was that good, you wouldn't give a fuck about the price drops right?
Whether we like it or not all the prices in this world are connected to USD in a way. I live very far from the US but when our local currency drops in USD, the people who are selling potatoes for example, the small farmers from rural places who really shouldn't care about the USD, they rise the price of their potatoes. I think that is because they keep their savings in USD and they want to get same amount of USD today for the sold potatoes as they got yesterday.