> Gen Z who are used to simple, powerful technology with simplified apps and UIs? why would they/should they put up with legacy UX and ways of working?

I disagree with the premise. The modern UIs are rife with more special cases, hidden gestures and non-transferable knowledge than the old “one mouse button is enough” or even early windows’ ugly but constant model. Gen Z has harder UI, over a superficial simplicity that is really just a constrained interaction space.

The problem for zoomers is now when they use a deep interaction model, the new complexity of UI becomes a frustration multiplier rather than fixed cost.

That and the visual language is so ambiguous and slapdash. Discovery is so much harder these days. And with every changing widget layouts, it's so hard to have a spatial memory if where to interact! Word in Windows 3.1 was far easier.