Seems if you can't go to exchanges, going to private corps or individuals who don't follow the ban lists would likely work, makes it their problem.

Of course, scale matters. Buying a couple of rigs off random sellers willing to take BTC should be trivial, but if you need a warehouse full of them...

which is how you launder money today! And dirty money is certainly worth less than clean money.

I was responding to the question of "how would it work?", not "is it worth 100% of the same 'clean' funds?".

Different circumstances and market conditions will make the discount variable.