the main problem: zero discoverablity - i need to google how to do things, then get some snotty fanboy answer about how easy and obvious it is, but there is literally no way to infer the functionality from the design.
they do love to steal context too... and interrupt your flow...
... i could go on and on, but having zero-discoverability is highly unforgivable, its an entire, rock-solid argument on its own.