And you still haven't explained how you would pay for ransomware over the internet via cash. We are talking here about the ransomers being in a different continent even.
And we have strict limits on cash to provide a stop of a complete abuse of it for criminal activities. Cash transactions over a certain limit have to be logged, there are physical controls at the borders as well as searches. So having a suitcase of cash cannot be concealed easily.
Yes, especially with local crime, there are cash transactions. That is regretteable, but cannot be avoided. The difference is, that physical cash servers a very important practical purpose: making legit payments easy. From using vending machines with coins to just paying for your groceries, you can do that easily with cash.
However Bitcoins don't seem to have a large practical values beyond the illegal actions. I am not aware of a large econommy based on Bitcoin transactions. It also can be shown that the pure time required to perform these transactions would be a hurdle. So most of Bitcoin is just speculation, the practical aspect largely based on the shady uses.
