Feckless democrats who want to appear tough on guns. Instead of taking on the NRA or lobbying groups they go after low hanging fruit to tout as victories to their base. It generates votes and wealth for the rep. Same thing with anti-trans bills from the right. Legislation that can pass through targeting small enough collectives that they don't have to worry about bad press.

All the news stories about ghost guns being 3D printed didn't hurt either. So they can sell a narrative of protecting people.