If bitcoin had a stable price it would be popular. Even if the price is stable or not the popularity of this bitcoin is not too much popular. Because many people dont know what is bitcoin. Many people dont need to use it. Many people dont have care about bitcoin. However it is not too much popular right now in the future i think this is the most popular coin even if the coin is not stable price.
But as time goes by bitcoin become popular to people because of its amazing price. As I can observe bitcoin is not very familiar to everyone because the price before us not really an amazing but if you notice people is now knowing the bitcoin because of its high price now. So I think one factor that bitcoin become popular is its price.