Devices being stolen are a real headache. The find my device is very helpful, but most of the time, thieves would turn off internet connection and would try to steal your sensitve data. Or just simply factory reset. Meanwhile all of us would have totally delete the information desperately. What if regardless internet connection, everytime a device is reported stolen, Google ban the mac address so it cannot connect to any google account. Therefore simply cannot be used, or in some devices at least not as their full potential. In chromecast devices, they do not have gps, I know. This is not to recover them (and let's be honest, a stolen phone, tablet, etc is most of the time never recoverd either). This is to disable them. So, anytime the home app is set to recognize the brand new factory reset device, it would perform the registration, but then go to check the mac address and simply disable it. Every time.
In the case of the phones, it would be glorious. This time the headache would go to the criminal, and it would return every time they try to register the apparatus.
A feature like this it would make me sooo happy. (I am a very vindictive person, I know