While I also hate the "undescoverability". It's possible that all (maybe not all) usecases of an app are still available to anything visible. For older or less tech interested people, this is actually perfect.
The problem lies in the following cases:
1) Person accidentally does something
2) Edge case / state / scenario, which cannot be solved without knowing some shortcuts.
I think iOS became too complicated for some people. At the same time the UI is a pretty messy and inconsistent at times.
The other problem is the flat design which makes it non-obvious which parts of the UI are tappable controls and which are just read-only design elements or indicators or labels.
Another issue is inconsistent placement. For example during iPhone setup, sometimes you have Continue buttons centered in the bottom half of the screen, and sometimes you have to tap the small “Next” label at the top right of the screen. I’ve had family members get stuck in that process because the Next button was so inconspicuous and so far removed from the main elements of the current dialog that it was completely unclear to them how to move forward.
In unfamiliar UIs, I often find myself accidentally triggering keyboard shortcuts and getting into weird states, so 1) leading to 2). A classic example is changing into override mode[0] in Microsoft Word or similar[1].
You end up in a mode where typing no longer adds characters, but replaces them. If you're at the end of the document, it would still add characers, but you stay in override mode. Meaning that once you're in this mode, it doesn't strike until you start editing or try to fix a typo, when the computer. WordPad doesn't even have any visual distinction.
Visual Studio Code's solution to this is nice. If you enter `Tab Moves Focus` mode, with <kbd>Ctrl</kbd>+<kbd>M</kbd>, the info bar shows the text `Tab Moves Focus` in a (tastefully) highlighted button, clicking which disables that mode. So you will have a moment of confusion upon pressing tab, inadvertently entering the mode, however the situation of 2) is avoided as a helping hand is visible.
Perhaps another UI is to have a log of activated keyboard shortcuts always visible, with 'new' shortcuts highlighted more obviously (perhaps with some estimation of decaying familiarity). I'm not familiar with this being implemented anywhere, but I think it at least merits consideration.
[0] This is activated with <kbd>Insert</kbd>; https://en.wikipedia.org/wiki/Insert_key
[1] In the version of Word I currently have installed, this behaviour seems to be disabled/removed. However, Wordpad still changes into override mode upon pressing Insert.
The problem lies in the following cases:
1) Person accidentally does something
2) Edge case / state / scenario, which cannot be solved without knowing some shortcuts.
I think iOS became too complicated for some people. At the same time the UI is a pretty messy and inconsistent at times.