I hope not.. No matter how new technology is, we can't remove cash suddenly at the year 2023. It's five years from now, I don't think they can make it.
I dont think cash will be extinct. It will depend on the leader or governments of that country. Not all the person knows about the new methods of cashless musty the indigent person they cant adopt or accept this new kind of the system. What if the internet connection got a problem? How can use it? However, being cashless also have good benefits at all I think we can reduce that corruption because of the transaction is can be seen by all the people.
as you say, I have thoughts that are almost identical to you, all depending on how the government is applying it or not, because as you say not many people are adopting the new method, of course the economic factors of each individual influence it, every individuals have different capabilities in viewing the user of the method, not to mention the required internet connection to be able to access it,
but for something like corruption, I'm not sure can reduce it, because sneaky people have different ways to get what they want