>Somehow at some point, in what perhaps could be blamed on the ever-hated mass produced MBAs - companies got really comfortable with the “it’s not personal, it’s just good business” of letting go of their employees for a slightest reason, or sometimes for no reason at all - just to make it look to their investors like they got their shit together.

Financial services (banks, investment firms, etc.) have been doing this for decades. It might feel revolutionary to a comfortable recent tech company existence, but I'm afraid to say this is the norm. Companies can hire quickly when they think they'll grow, and fire en masse when the tide turns.