It seems to me that so far it is not worthwhile to compare bitcoin with real money, this is the same as asking what is better bitcoin or ether? Everyone has their own ways of applying which can not yet replace.  Bitcoin is a crypto currency and it is comfort to use on online and fiat is better to use in open world. 

Cash will almost always be king because it is an accepted form of currency literally almost anywhere. However, there are not a lot of places where you can pay with Btc. I have only seen one place. It was a sauna in Toronto that accepted Bitcoin.

Also speaking in favor of cash, the fees for making these or those transactions are more convinient, what I cannot say about Bitcoin