The manager maybe, but you don't change the culture of the company like that. A low level manager has very little influence on that, they'd be replaced the moment other VPs started complaining.

Depends on the on the exact political arrangements. I’ve seen a “low” level manager get the ear of a senior leader and get protection/empowerment that ended them to do something on par with this. It sounds like the author got the appropriate buy in, and I suspect that not all ad hoc work got prioritized in a FILO manner.

It sounded implausible to me. Admittedly I don’t work for a large corporation but this sounded like a socially challenged persons dream of how they’d convince large groups of opposing people to their side. Hostile interactions with shelter from an all powerful HR and the vague threat of a lawsuit.

I've explicitly asked for strong barriers from external leads and developers from my manager before and gotten them. My current boss aggressively puts barriers in place to keep us from being bothered or distracted.