Yes, but Mac OS 9 (and any MultiFinder version of the classic Mac OS) at least presented the illusion of multitasking. And it did multitask, as long as the apps cooperated and handed off to each other, and an extension didn't go bang or smash into another one, and ...

But, jokes aside, I still got a lot of work done in Mac OS 9 back in the day, so it wasn't nearly that dire even if it was best not to peek under the hood.