The problem is that this should have been created at the beginning of the Bitcoin civilization. They say that the code is open, but it really isn't. The code can only be copied or viewed, but it can't be rewritten. When the code is open, it can be modified, but Bitcoin's code can't be modified. Bitcoin is controlled by a dozen programmers spread around the world anonymously. And the reason why this can't be done is that every block from the beginning would have to be modified for this to happen. And this can't happen in a blockchain unless it was programmed from the beginning to do so. We can come up with a plan and get away with it, but it wouldn't be with Bitcoin.