Which physical objects that you make in your home, are actively monitored by the police as you make them? When I bake something in my oven, would it be reasonable for the DEA to have a camera in my kitchen to ensure I do not make weed brownies?
I think you are a little confused because the title is a little bit editorialized, but, this law doesn’t monitor anything in anyone’s home. It controls the commercial sales of 3d printers.
"This bill would require, on or before July 1, 2028, any business that produces or manufactures 3-dimensional printers for sale or transfer in California to submit to the department an attestation for each make and model of printer they intend to make available for sale or transfer in California, confirming, among other things, that the manufacturer has equipped that make and model with a certified firearm blueprint detection algorithm."
This in my opinion is the state monitoring me in my own home. You can split hairs on semantics, but the effect is the same if machine learning or a person does it.