Laws limiting firearms with "undesirable" features are already on the books. You can own a Thompson sub-machine gun but you have to go through ATF licensing to get one. Costs and the "rules" make it not even worth trying. If you do own one, your local sheriff must be made aware of it. When transporting it, you have to notify the sheriff of each county you carry it through. That sheriff could confiscate it for any reason and without cause. I saw that happen in Vilas County, Wisconsin.
The owner of a Thompson notified and presented the Vilas County sheriff with the gun. That sheriff promptly confiscated the gun. The owner had NO legal recourse. The reason this sheriff confiscated the Thompson? After he legally took it, he promptly hung it on his office wall for decoration. Like it or not, that's a fact and happened in the 90's.
The laws are no different now. All Biden need do is declare, with the ATF, any AR15 based/M4 variant rifle is subject to the same rules as that Thompson. You better hope your shooting range is in the same county where you live! You better hope, too, that your sheriff is gun friendly sorta fella.