* It's the experienced users who were were less likely to recognize the "burger menu" or the three dots (does that have a catchy name) as something potentially useful. They didn't look like "real" controls. It was the less experienced users who just naturally tried clicking on anything near the top that looked interesting, or waving the cursor around looking for hovertext on active components.

* Confronted with a landing page that seems to have nothing more than some splashy graphics and a few words - notably no scrollbars - experienced users are likely to wonder if the page is broken for them (because that was a very common experience at the height of the browser wars and still persists). Less experienced users who grew up with smartphones are more likely to start swiping right away.

A user who was older but not experienced with computers would align more closely with the young 'uns on most of this. When everything's completely new you just start experimenting. It's when you think you know things work but they don't work that way any more that things start to get frustrating.

Hell yes. In most instances, I'm way beyond this point at only 30 years old. Come to think of it, it actually makes me wonder how I will feel about UIs at 50 or 60 years old.