The 2016 layoffs was the same way: they looked at an org chart with salary + seniority and started at the top, sometimes cutting the one person who had been with a product for years. I heard the exercise was from HR and not the businesses (so don't blame your boss ... s/he has little choice in the matter).
And unless you can get hundreds of people organized to not accept severance packages, then there's no chance you'll get an age discrimination suit going. In 2016 the statistics were quite clear: they overwhelmingly cut people over 40. I forget the exact percentage, but it was high. But what are you going to do about it? You need a lawyer who's somehow going to publicize the case and let people know they can join the suit, etc.... There's just a slim chance it will ever happen. And in the US -- forget it. Never gonna happen.
Bumped from @VdoDvSb-deft.