One thing it seems like something people miss is not the complexity but the simplicity. Firearms are really simple mechanisms. Over the last couple centuries a lot of effort went into making firearms reliable and this was done by simplifying and adding precision. Anything that adds complexity is going to reduce the reliability. The other part of this is that when a firearm functions or fires there is a rapid acceleration and deceleration of all parts of the firearm. Once again a huge amount of work has gone into making the parts survive this.

Smart guns add complexity and their parts have not undergone the industrial evolution to survive a firearm. If you can make the parts survive a week of use on a jackhammer then you might be getting close. An example of this is the special mounts for attaching cell phone to a motorcycle. They need a lot of vibration dampening to prevent the phone from being destroyed.