winapi introduced event based programming to the masses and took it to the next level. You could argue that they weren't the first, but blanket singling it out as bad design makes no sense.

This control flow has been taught everywhere and is the basis of node's async loop (node waits on io, winapi waits on kb/mouse/timers) so "no system copied it" is complete ignorance. It is the first thing I think of when I'm designing an async flow.