That is an extremely interesting point of view, thank you for sharing. Another thought: say some criminals pass their money through a mixer and like in the scenario you described, it's deemed worthless to any exchanges/payment processors because it's "dirty". Does this mean that, say they were feeling sour they couldn't book a hotel on Booking.com, could they potentially taint any public wallet address by sending tiny amounts of bitcoin from their tainted wallet to them? Can a user prevent/block coins being transferred to their account in the blockchain? If your prediction comes through, this could spell a disaster for Bitcoin because potentially every wallet could be tainted and thus all coins traced back to criminal activity.

As a side note, it's interesting to think that those "dirty" coins/wallets will be destined to circle around the black markets forever.