System 7 checked for mouse motion every fraction of a second and if the mouse was moving it would drop everything and draw. It didn't need apps to yield for this to happen.

Are you comparing that shit when you pulled down a menu in System 7 could bring a whole network down, with Be? Such as a good joke...

The CPU and the whole net by holding a menu item down.

That was arguably an application specific issue, though the OS was painful to code for. I actually coded some classic Mac OS networking code and it was insanely easy to mess things up, but eventually it ended up being rock solid. The trick was all level interrupts where supposed to only do almost nothing. You couldn’t allocate memory for example which was a major hint of just how minimal those functions needed to be.

Worse with cooperative multitasking any running application could mess things up.

Then do not talk about Classic Mac as something magical because compared to Be they were utterly ridiculous.

For its era, System 7 was good, but later, it was worse than even Windows 98.

Be tried to do things right, it was ~1995 after all.

I see where java gui coder took their inspiration from /s