That is underway, with adult content providers (for example) now generally accepting payment methods that do not rely on credit card companies. All the way to accepting Home Depot gift cards that can be bought for cash.

The issue is that for now, and for a long time ahead, all these content providers feel that most of their clients would prefer to use a credit card. So they need all of their content to be acceptable to these people. Which comes with lots and lots of lowest common denominator rules. Even if some people do not use credit cards.