The crashing has been due to a combination of default motherboard settings and user settings with Intel not putting enough restraints on the both of them.
Ryzen chips can also be abused by the user, but after the X3D explosions AMD cracked down on motherboard vendor shenanigans. Intel is also locking down the mobo vendor default settings on the next gen.
As far as voltage induced degradation, both Intel and AMD CPUs behave the same. And yes, Ryzens can and do degrade, Zen 2 has a lot of posts about this. If you bought a used one and it doesn't work at stock settings then it is faulty and you have Ebay policy. If it does work, but is degraded to some unknown amount it doesn't degrade more unless you give it degrading levels of voltage.