It's like typing. Learning to touchtype was one of the best things I've ever done on a return for investment basis. All I did was stick a little printout of the keyboard layout under the monitor, and committed to not look at the physical keyboard ever again. It was slow for a couple of weeks, but from then on I could touchtype. It was not such a massive burden. But most people I see are still painfully hunting and pecking, even people who use a computer all day long in a professional capacity!
I know there is much more that Apple and other manufacturers could do to make things better, and definitely they should be doing those things, but the main problem IMO is that people are just lazy. They want their phone to do complicated things, but they don't want to spend the time to learn how to do those things.
It would be good if there was easy training for these things though, maybe some kind of beginner courses? I know some community centres/libraries have courses for beginners and older people... But most people just expect to automatically be able to use a smartphone with no training, knowledge or effort.