We've known about Fitz's Law since the dawn of the GUI and have decades of study on it. It's not any more efficient to need to "headshot" everything you need in an application 100% of the time, and in fact it is often rather the opposite that it gets in the way of actual efficiency.
Mousing through most "mobile" applications is great, whether "first class" or not.
Desktop and mobile OSes don't need to remain separate, and it's really past time that a lot of super-cramped "desktop apps" got the death they deserved for their decades old RSI problems, accessibility issues, and garbage UX.
It's friendly but it's not space efficient. For applications with a huge number of features, a touch UI can't handle them. Touch screens don't have right click, so you can't get context menus.
It's more than that, though. A touch screen UI for the iPhone makes zero sense on a 32" display. I'd much rather have a true multiwindow, multitasking operating system than that. Really, I wouldn't use a 32" iOS device at all. That's probably why Apple doesn't make them.
User studies from the dawn of the GUI continue to harp that user efficiency is inversely correlated to space efficiency. It doesn't matter if an application can show a million details to the individual pixel level if the user can't process a million details or even recognize individual pixels.
> Touch screens don't have right click, so you can't get context menus.
You don't need "right click" for context menus.
Touch applications have supported long-press for years as context menu. Not to mention that macOS has always been that way traditionally because Apple never liked two+ button mice.
Then there's touch applications that have explored more interesting variations of context menus such as slide gestures and something of a return to relevance of Pie Menus (which it is dumb that those never took dominance in the mouse world and probably proof again that mice are too accurate for their own good when it comes to real efficiency over easy inefficiency).
> I'd much rather have a true multiwindow, multitasking operating system
Those have never been mutually exclusive from touch friendly. It's not touch friendliness that keeps touch/mobile OSes from being "true multiwindow/multitasking", it's other factors in play such as hardware limitations and the fact that tiling window managers and "one thing at a time" are better user experiences more often than not, and iOS if anything in particular wants to be an "easy user experience" more than an OS.
(I use touch all the time on Windows in true multiwindow/multitasking scenarios. It absolutely isn't mutually exclusive.)
Sure they can, but why bother? When I use Windows, I use real Windows applications with desktop UIs. The touch UI mobile apps are a joke on a desktop monitor.
Desktop and mobile OSes should remain separate. You don't go around hauling fully loaded semi trailers with a car.