I read a commentary years back about Google's social efforts. The author blamed Google's failings on the author's assumption that no one at Google actually used their social products. For comparison, it's obvious that Google uses gmail throughout the company, and therefore has practical insight and inherent motivation to make it usable.
I've been saying for many years: I am 100% convinced there is no one at Apple who lives and works on an iPad (small caveat: without having it permanently tethered to a keyboard).
1. Text selection is awful: it takes an eon to select a word in text on iOS compared with double-clicking a word on Mac.
2. God help you if the insertion point is just a character or two away from where you need it: you either have to do the long-press on the keyboard, then carefully drag to correct it, or tap somewhere else completely and then tap where you want it.
3. If iOS thinks it knows where you want the insertion point, it thinks it knows better than you where the insertion point should go. See (2).
4. Selecting large amounts of text is a huge pain.
5. The touch keyboard just isn't viable for use at scale.
I could go on, but it's just a rant and no one at Apple is reading this, so I'll stop there. Apple, if you do happen to read this and want to fix this, hire me!