I think its more that positions of power attract power abusers. I absolutely do NOT think that 'mods turn shitty due to burnout', most power abuser mods are shitty people before they attain the power, and actively seek the power to expand their ability to be shitty to others.

Without rigorous vetting, these slots will always be filled by the most eager sociopaths, and seeing as anyone can be a mod by making a community, there is literally zero vetting at all.

ALL of the admin interventions happen after a mod exposes their shitty behavior, and we know that sociopaths are ridiculously skilled at making themselves seem the victim when they are actually the aggressor.

Actual good mods see this and are disheartened, because what's the point of working hard to support a community when their mod peers destroy their work with their sociopathy.