Whether it actually gets enforced doesn't matter, what matters whether people refrain from engaging in the activity (or aiding others in doing so) because of the risk that it could be.
There's always that risk with unenforced laws - there's hardly ever (ever?) a stated policy of non-enforcement, since the executive is also technically obliged to enforce everything congress has told it to.
I would generally be interested to know if it ever has actually been enforced so far.