That's irrelevant. It wasn't an issue before and is now. I have written two best selling books on iOS and OSX, am just over 30 and have been using iPhone since 2008 and iPad since 2010 (so I'm a pretty knowledgeable user) and yet I find some major UI/UX changes in 10 baffling and inelegant, even after four weeks of daily use. Cognitive load is higher in 10 than it used to be. 9 introduced some additional complexity with 3D Touch but throes were just shortcuts - users didn't have to know about them. But in 10, basic things like unlocking, notifications or control center are a point of confusion. It's not just a thing of habit - if a single action requires two or more different approaches based on multiple contexts, the design is not good.