Honestly I believe bitcoin is better since one you don't use your credit card so you don't loose you needed cash but instead your cash that you could easily earn back from mining. Plus, it's open to all ages unlike credit cards.
There are still people who don't use or don't even know what is bitcoin even you say that it is open for all ages, the question is, it is afford by all ages? There is a probability that you will loose your online or offline wallet and it is hard to recover all the money worst you can't take it back unlike on cards you can still remind the banks for the loss of your money. But I didn't say that go for cards not to bitcoin, its just be practical according to your social strata.
Cryptocurrency and ordinary currencies are two very different things. So I think comparing these two things is a hassle. Both have their utility, uniqueness, and superiority.
I'll try to give an example, I personally use
Bitcoin just for as an investment tool, nothing more. But I still use ordinary currency as a tool to pay bills and food everyday. I do not use
Bitcoin for shopping because
Bitcoin prices are always up and down. If I use
Bitcoin when the price is going up it will make me lose. I'd better save the
Bitcoin and wait for the price to go up.
The problem about anyone who can use
Bitcoin, I think everyone can use
Bitcoin. Even kids in
Junior High School and
High School can also use it.