I think my explanation is at least as plausible as yours with the added benefit of not denigrating an entire group.
>tend to get burnt out
People can also just overcommit to volunteer activities in general for a period. If people can just dial down their involvement, that can be OK. But if it's an activity that's all-in or nothing, it probably won't last for more than a while as people burn out or their priorities just change.
Obviously there’s exceptions, but it is a really common phenomenon. They found communities or get modded simply because they spend the most time and hang out in the right chats, not because they’re objectively great neutral moderators. They are very frequently people with very strong personalities, and are often in the long-term have a more destructive influence on communities than any short-lived comment troll, especially wrt to the effect on newcomers as they tend to make communities increasingly insular.
These same people, are just overstressed and take too much shit, and this explains the vast majority of all alleged abuses?
I've heard this before. I hear it every time someone is shot to death while crawling towards their attackers while being screamed at to not move and come closer simultaneously. Every time that someone dies with a knee on their neck for 10 minutes. Every time a grenade is thrown into a baby's crib.
That's about the most generous I can be. Reddit moderators have not actually thrown grenades into baby cribs. They're not quite as bad as those that do throw grenades into babies' cribs.