I'm not sure what services PalmOS provided to the apps, but to my limited knowledge the apps themselves were non-multitasking, and had a standardized database per each app instead of the filesystem (i.e. something like proto-IndexedDB, but more oriented to documents or blobs). So it's kinda difficult to imagine them having the problems of quasi-multitasking and more complex MacOS. But perhaps things became involved by PalmOS 5.

Though the event handling part sounds like DOS' raw approach, versus Win95's abstraction—and I guess could plague any kind of a system.

> What Microsoft wasn't ready for was the hardware getting so good that Apple could just port their existing desktop OS and software over.

Eh, I mean, MS attempted that more that once themselves: though WinCE wasn't Win9x inside, it sure looked like one, and purportedly even had swap.