Yes, if I remember correctly, Maryland uses it to solve all of their semi-auto gun crimes. Whoops. Maryland spent 5 years and $15M and didn’t solve one crime. Oh, never mind.
The bad guys can just use a revolver. Problem solved.
Maryland did not use micro-stamping. It required a fired case from each handgun to be sent to the State Police to be imaged and put into a database. The idea was that ejection markings could be used to identify the gun. In the years they had the program, they had one match.
Soon enough the State stopped scanning the cases. They just threw them all into 55 gallon drums. Finally, the regulation was repealed.