We are talking about the future of Mastercard or Visa, which is currently still in the speculation stage. There is no definite answer about that. But it's okay for discussion.
Mastercare and visas are generally issued by government-owned companies or banks in each country. Of course, what is an asset of the government will be maintained.
We know that the existence of crypto today really helps transactions and guarantees security in the developed blockchain system. Then why is it still difficult for the government to accept crypto, isn't that something good.
If something new becomes commonplace in society, of course what happened before will be abandoned by society.
If the government accepts the blockchain system as the main transaction route, of course transactions at banks will stop, including Visa and Mastercard, and that will be detrimental to the country.
Considering how "huge" those two companies are, I am %100 sure that we are going to end up with a lot of trouble if we end up with anything else then these companies figuring out a way. I mean they will probably have hard time if we just use our apps, because banks would be able to just directly deal with it, without needing cards.
To be fair there were a lot of industries and companies that used to be rich or at least do well, but then no longer needed because technology improved. Like back in the day we had phone books where you looked at a yellow book to find a number, or had encyclopaedia that everyone had in their home back in the day, none of that exists anymore and that is why it's maybe time for visa and mastercard to slowly bankrupt too, who knows.