The problem with going cashless is that not many people will be able to embrace it. in the advanced countries this may not be such a big deal as nearly everyone is already familiar with all sort of technology and buying online in a cashless manner. in the developing countries with high number of uneducated people, this can be a very big issue, it will require teaching almost everyone on how to operate an internet enabled device and own one as well.
Going completely cashless will pose a lot of challenges to many people which i doubt the governments are ready to subject its citizens to. So this is not advisable best thing for now is operate in both ways
Now we are talking about the transition to cashless payments in developed countries. In the last 5 years, I have noticed how much the attitude towards cashless payments has changed. 80% of all customers pay by card. I myself prefer paper money, in this regard I am conservative.