That is precisely the question. Apple has defined hardware models, so you can easily configure a backup for your hardware.
But this isn't about the hardware surely, it's about backing up an SD Card and the data on it. I could have a massive complicated server or as I have a raspberry Pi 4 with a couple of drives attached, but if its OS is just an SD card then all you have to do is back up that. If my SD card dies, I am royally screwed. I'd feel much more comfortable knowing that that little SD Card was "automagically" backed up in case it does die