It's more that white markets won't want to deal with the risk of tainted funds because of increasing regulation. Tainted coins might not be accepted or undervalued at other places for the same reasons. So businesses and people will either refuse them and ask for coins with "clean" histories. Or they will accept them for a discount.
I think Bitcoin/Monero were always meant to be black/gray market money.
I just feel more cynical about it and don't see how this isn't the outcome. But I rather have what you are saying be true.