I've heard it asserted that your median level of talent doesn't change much with these strategies. But that means you're losing people that you could probably ill afford to lose.
But what actually happens is that a few of the lower quartiles leave, and at least as many from the upper quartiles leave. None of the Dunning Kruger people leave because they’re all that and a bag of chips. So you tend toward mediocrity. Doubly so because when the changes that management expected don’t happen, now everyone knows there is likely to be a round of involuntary layoffs. So the people you have left either start playing it safe or become demotivated, further lowering the stuff per dollar. And now the company is doing worse, and some idiot upstairs thinks it’s just their predictions coming true, instead of self fulfilling prophecy.
Not that I mean any of this as a lecture or warning for Zuck. More like a movie trailer. I hope it all burns and we get to watch it happen. But more likely they’ll turn into Microsoft. Fewer teeth, but still essentially the same bastards they always were, because changing a negative founder culture is really, really hard for any social or business group.