I'm not sure it is easy if you've never typed before! Pecking away letter by letter isn't easy - and added to that, there's often a problem with impaired vision. The free versions of speech-to-text are a bit shonky (I tried them all for my mum) and, anyway, talking to a machine doesn't come naturally at all. Even my Echo's quite bad at understanding natural language, and it's supposed to be the best in class.
It isn't very easy to get used to a mouse - move this thing but don't look at it, look for the little arrow moving on your screen. Touch screens are even worse: think how often you, an habitual user, open the wrong app by mistake, accidentally close a tab or navigate somewhere you didn't mean to!
The whole business of using one app/program for one thing and another for something else is far from intuitive. Then there's things like menus and bloody icons everywhere that you have to know what they're (probably) for. I've been online since 1992, have built many websites and user interfaces, and still get exasperated by tricksy navigation.
There's logging in, authentication, saving stuff and finding it again, understanding how online orders and payments work, how to check if you already paid, how to see if you ordered correctly and what to do if you didn't.
I tried building a super-simple launcher for mobiles but soon found it could not actually be both simple and reliable, due to the limitations of the apps. Last time I checked (about a year ago now), no-one had yet built one that would actually work well for a user of limited capacity. Some companies offer custom 'elderly friendly' tablets; they're crap and overpriced, with a compulsory subscription to their helpdesk service (which tells you everything about how easy they really are to use!)
Practically no websites meet accessibility standards, and they're getting worse not better. Erm ... I could go on but this is already longer than I intended 😬