I can see the benefit of a chip that can be read electronically, by eyeball, and optically by machine, but I agree that the latter necessitate something large that is not going to price/space friendly.
I think what is commonly done in manufacturing environments is that as part of the program/test plan, a decal is generated with serial number read off the chip on it. The decal can then be applied to the box, the outside or inside of the case, and stored on a computer.
I worked for an IoT company that did this. When configuring the product, the end user had to enter the code on the box which was a hashed version of the serial. This meant that someone else couldn't easily reconfigure your hardware. And when the device phoned home the first time, that value was compared with what we had on file to keep coutnerfeit hardware off our systems.