I would expect the rate of compliance to such measures will be about the same as the actual compliance rates for the so-called 'assault weapons bans' enacted in recent years. Last I heard, the actual rates of compliance have been estimated at no more than 15% to 20%, which means that 80% or more of the population will fail or refuse to comply. Yes, those folks are taking a significant risk (facing possible prosecution for felony charges), but this should be instructive for the elected and appointed officials attempting to enforce such bans.
Seriously, if a given state has 100,000 citizens possessing banned items (large cap magazines, bump stocks, or whatever), and only 15,000 to 20,000 voluntarily comply with the bans, that still leaves 80,000 to 85,000 newly created criminals. Does any state have the means for arresting, detaining, trying, or incarcerating an additional 80,000 people? I think not.
More than ever before, now is the time for people to band together and share resources to fund legal defense efforts and legislative initiatives. Those who would strip us of our rights can easily pick us off one at a time, but no state has the resources to handle large scale peaceful civil disobedience. Just 50,000 like-minded people each contributing a $100 bill would immediately create a $5,000,000 fund to fight every inch of the way in the courts for anyone who is ensnared by the system. No guilty pleas, no plea bargaining, no compromise, every possible legal method employed to make each case a legal nightmare for the state(s).