Earlier quoted context omitted.
You're being ridiculous. Emergency reverts are normal and expected when production systems are down. I'm willing to stipulate this person's specific actions were probably hostile and unwarranted, but some sort of blanket "no revert without discussion" rule is just a way to cost your employer customers. Context is important, and we don't have enough of it to be certain of what happened.
You're right, context is important. But where I work we provide an explanation when a commit is reverted, emergency or not.
In both cases, I wrote a detailed technical explanation of why I had taken the action, and an apology for having to do it so suddenly, and I sent to to the entire group (a requirement anyway - if you make an on-the-fly ops change, you need to write up a full incident report so everyone knows what went wrong)
Reverting always needs to come with a "this is what was wrong".