The entities that want gun control don’t care about black markets. They want to limit the ability of the law abiding citizens to own and obtain firearms.
They aren’t stopping at enhanced background checks, limiting of features, firearms taxes, ammo taxes, waiting periods, training, psychology exams, and those sort of things. We’ve gone past “No one is coming for your guns” and “common sense regulations” and we’ve arrived at no guns for citizens as the goal.
It may take anywhere from 10-200 years to make us law abiding people gun free, but it will happen.