Maybe, not impossible but will take a lot of time i guess, there are a lot of people who has less knowledge in technologies, once their generations passed, blockchain tech will soon be known by the world and that time fiat may be out-valued by cryptos.
I dont think that will happen. But we cant predict. Maybe that will happen but for me there are so many disadvantage of digital money. Whats wrong with fiat? I think thats enough to use and digital money to be use to buy things online.