The most favorable explanation is that they didn't really think it would be permanent. They just needed the headcount at the time, and they don't need it anymore. The rest is just marketing spin to not make it seem so bad.

Now if they all balloon back up to the same headcount in the next year, but with lower salaries, then we will see if the real motive was to lower salaries. Someone had posted on another thread that the federal reserve stated that the goal of recent policy changes was to lower salaries. It's much easier to layoff and rehire, than it is to give out paycuts.