is bitcoin more popular than US Dollar ?
It depends on the environment that we're talking about,
If we're talking about reality absolutely the dollar is the most popular money of all but at the level of the virtual world I think the bitcoin dominates !
No dear Bitcoin is not more popular than US Dollar, because not more people aware about Bitcoin or even they never heard word Bitcoin, but after ransomware attack more people came to know about Bitcoin, one day may be Bitcoin in lead.