Hi. I'm a Microsoft employee that survived/thrived during that period and I'm not a ruthless piece of shit. Also didn't do it by tearing down others.

Mostly kept my head down (though I'd rock the boat if it was really necessary) and did my job. Also helped that I took ownership of some legacy code that was critical to some part of our team, and there was zero documentation for it. So basically I made myself indispensable! :)

But many of the more recent Microsoft layoffs have not been performance-based. Instead, they just decide to end entire projects. Even if you're a rock star, you still have to go through a round of interviews if you want to move to another team.