Re: I am surprised there's anyone left to lay off!
They're usually still hiring while they're laying off. Still buying other companies. They (most companies, that is) don't often mention that part, or if they do, they couch it in some corp-speak double-talk like "re-focusing the workforce" or similar.
In spite of the impression created, layoffs don't always shrink the workforce. It wouldn't be a huge surprise if the overall headcount is higher in a year or so.
Layoffs are typically a (temporary) way of juicing the stock price or the quarterly results, or simply to make it look like the big wheels are doing something, in front of the board of directors / shareholders. The other effect is to swap some (usually higher-paid) longer-term and probably older employees for hopefully younger and cheaper models, who are more pliable to overwork and other management abuse. That's never a stated goal, of course.
That turnover comes at a price, of course, and I'm not referring to the severance packages. Even if the layoffs are carried out perfectly (and they never are), such that only the "low performers" are let go, management have still churned the workforce, causing all manner of chaos and dysfunction. Tribal knowledge and experience has walked out the door, either with a severance package or on their own, because they've seen how the company treats people and "enough is enough" etc. The ones left behind are nearly always left with more work, less resources, and less motivation. That severance package starts to look pretty good after a while.