The problem with 1-3 is that they only work because regulators haven't tried very hard to stop them. If you require crypto exchanges to verify that funds in acc

The problem with 1-3 is that they only work because regulators haven't tried very hard to stop them. If you require crypto exchanges to verify that funds in accounts are not coming from these types of sources before allowing you to take fiat out you've now vastly reduced their usefulness to the degree that only sophisticated criminal participants have any chance of actually getting usable money out of their schemes.