Many financial institutions did everything possible to get people on cashless policy until they got tired because they kept meeting less interest of people, and those who picked interest found it easy to adapt to the system. To me, there is nothing too difficult to adapt to in the system of crypto, it is just lack of interest that I see
When money talks, bullshit walks
People are not interested in cashless payments because there is nothing in it for them, although this is not quite true. Many banks are offering nice cashbacks if people are paying with their cards. That's one of the reasons Bitcoin and other cryptocurrencies have become so popular as they allow an easy and free access to trading places for all (whether people can actually earn something there is another question)
On the other hand, it is not so much lack of interest itself as psychological inertia, i.e. "the reluctance of doing something in a different way as you have an indisposition to change" (as per Wikipedia). In simple terms, people don't like change and don't like to change. But once forced to some activity, they may find it quite interesting and appealing afterwards