Is losing a CPU a common enough failure-case that it makes sense to implement fail-safes for? I would think that's pretty low on the list of likely causes of failure.
I mean it's more than CPU - losing power regulators, or anything else that causes your machine not to boot to a DFU mode. Watch Louis Rossman's channel for long enough and you'll see how many possible failure modes there are.
My 2014 MBP died a few years back of power regulator cause, but I was able to pull the SSD and image it in the case that they were unable to repair the device.
I lost three Macbooks in two years from USB controller blow outs, which is a known issue because the part they used is lousy, and it took out the entire storage with it. I had some backups thankfully, but I know people who have lost everything.
My 2014 MBP died a few years back of power regulator cause, but I was able to pull the SSD and image it in the case that they were unable to repair the device.