How come you make a conclusion that we are in a bubble,only using this comparison?
I don`t understand your theory.Bitcoin can`t be compared with cash in circulation,because most of the bitcoins aren`t in circulation.Most of the btc are owned by HODLers ,who refuse to use them and only wait for the price increase ,when they sell them for USD to take the profit.You have to compare BTC in circulation with USD in circulation.
I don't think you fully understand what OP is trying to say. If you call the rise from $600-$10000
then I don't even know what to say. We clearly are in a bubble, sans the comparison of cash circulation with BTC. Astronomical growth within a short period very well defines a bubble with only a few million people utilizing it. Current number of bitcoins in circulation won't affect the total marketcap in any way since all mined coins are still taken into account even if they're lost forever.