It is not possible for the game to permanently or substantially damage a computer that is in proper working order. That last part is something that I see being missed a lot in discussions.
If your PC is supposedly damaged by Helldivers 2, it is not the game's fault, and it can always be traced back to some other underlying issue, be it user error or improper installation. 90% of the time, the only way software can damage your PC is through overheating. Your hardware has safeguards against this which can and will override the game and your operating system. A correctly built PC should never exceed dangerous temperatures for prolonged periods of time, and if a program is capable of doing this, it is your fault, and merely a coincidence that Helldivers 2 was the program that happened to be the final nail in the coffin.
And no. Kernel-level is still restricted to your operating system. BIOS and other firmware on your physical PC components can and will override it. Gameguard cannot force your PC to run itself into the ground, unless you (or the manufacturer in the case of prebuilt computers and laptops) have modified it to operate outside of what is normal.
So no, the anti cheat cannot damage an unmodified PC with no underlying problems. This is not Helldivers 2's problem, this is your problem, and any program can damage your PC if it is having these issues.