I'm sorry but this is just a fundamentally incorrect take on the physics at play here.

You unfortunately can't ever prevent further breakdown. Every time you run any voltage through any CPU, you are always slowly breaking down gate-oxides. This is a normal, non-thermal failure mode of consumer CPUs. The issue is that this breakdown is non-linear. As the breakdown process increases, it increases resistance inside the die, and as a consequence requires higher minimum voltages to remain stable. That higher voltage accelerates the rate of idle damage, making time disproportionately more damaging the more damaged a chip is.

If you want to read more on these failure modes, I'd recommend the following papers:

L. Shi et al., "Effects of Oxide Electric Field Stress on the Gate Oxide Reliability of Commercial SiC Power MOSFETs," 2022 IEEE 9th Workshop on Wide Bandgap Power Devices & Applications

Y. Qian et al., "Modeling of Hot Carrier Injection on Gate-Induced Drain Leakage in PDSOI nMOSFET," 2021 IEEE International Conference on Integrated Circuits, Technologies and Applications