And the supervisor's supervisor.

"I see you had ten underperformers that you have kept on. Didn't you know our company is working hard to save money? I've taken the liberty to fire them, consider this your first warning."

Even the best managers will have a hard time trying to convince upper management that people who miss quotas are worth keeping on.

Again, nothing new here. Quotas are already measured by queues filled, boxes moved etc. This is not a game-changer, just a cost-saver.

Do you also hold the belief that it's OK for three letter government agencies to proactively collect intelligence on all US and foreign citizens, because they could do it previously using tails, phone taps, and cameras?

As you say, quotas have already decided many a employees fate. The difference now is the scale at which the lack of human judgement can be applied. Scale can only hurt affected employees; it can never help them.

You seem to have an unshakable belief in the people you have worked for and hired and their ability to treat their low-paid hires fairly. I've personally had that belief burned away by the realities of working in a minimum-wage job.