Now that more and more countries are starting to go cashless (
http://www.bbc.com/capital/story/20180427-does-a-cashless-society-benefit-everyone), is it possible that we also start converting to cryptocurrency? If that happens, what do you think are the advantages and disadvantages? Paying virtually is very convenient for me as I do not have to bring cash and it prevents petty theft but what is the disadvantage?
No state can fully switch to using cryptocurrency only. If this happens, especially in many states, chaos will simply begin and the economies of the states will collapse. Therefore, no state will ever fully switch to the use of cryptocurrency. Cryptocurrency can go in the state only in parallel with the national money of this state.
It seems to me that some people have very unrealistic views about what cryptocurrencies can achieve, it is true that the invention of satoshi was incredible but like anything it has limitations and one of the most important is that it's going to be impossible for everyone to use cryptocurrencies because you need to have access to a computer.