Aside from what I mentioned before, surely people would still be able to do P2P trading like those usual bank transfers that can be done either direct DMs to people. Government would go so far into putting people behind the bars just to fully stop them from using any forms of crypto at all.
You are right, when the central bank banned accounts linked to cryptocurrency, people where still buying and selling bitcoin through P2P, am sure it will be very difficult to dictect, if you are buying bitcoin and you are sending money to the seller, their is always a space for remark, most people using P2P where warning their customers then to stop using anything related to bitcoin or cryptocurrency as Remark, since the remark is optional they should leave it empty. Am sure only people from my country will easy understand it.
What country are you from by the way? I am quite familiar with the old news of a certain country having their banks ban crypto-related transactions. Was it really that bad of an effect to your country? Banks here in my country (Unionbank to be particular) even launched crypto trading into their app.
Am from Nigeria, it was all banks that where banning accounts linked with cryptocurrencies or bitcoin, but some banks are strict why some are not really strict, I heard some banks had agent's on binance P2P, if you can trade with them, they are going to report your account directly, I don't really know how true that was, but then I decided to trade with agents that have stayed long on binance P2P.