Some Intel Atom processors die after sending more than a few terabytes over USB over their lifetime. You can easily kill a laptop by leaving the webcam on for a few weeks, and then magically all USB stops working and there is no fix other than soldering on a new CPU.
The USB issues were related to a critical flaw in the LPC clock, according to the Intel errata. USB expected lifetime traffic for the affected processors was 50 TB while active at most 10% of the time. The errata implies lower voltage systems aren't affected.
To me that says simple design flaw. Something like overdriving a transistor to get more performance out of it, without realizing what relied on it. That will cause slightly different failure conditions from electromigration.
Possible, though Atom had it's share of non-aging related problems, too. Ugly race conditions, etc., though I believe the older Atoms were immune to Meltdown & Spectre vulnerabilities.
I wonder if this is the reason?