> Shortage of devs is (was?) a very popular talking point, but is it really true? If each developer was so unique, special and valuable, would companies be laying them off now?

When companies were executing on projects that required workers and couldn’t find them, yes there was a shortage. When companies cancelled several projects and had extra headcount, they let workers go. I suspect in the not so distance future the very same companies laying off workers now will need more of them, and that will be even more difficult than today.