I'm in that group.
It's not "getting used to", I feel like that gesture is less practical. It involves or using the "circle" to assist on how to use the gesture (creating a black void on the screen that you need to plan your use of the phone around) or having the swipe that 1) is not as reliable in my opinion and 2) can be triggered accidentally
For me is like claiming that touch screens on cars are the future and people are too old to get used to it.
Maybe saying "too old" is disrespectful indeed, what I meant was more that my kids grow up with swiping everywhere but we grew up with (hardware, then touchscreen) buttons and the older we get the harder it is to get used to new use paradigms.
Swipes are of course nice because they allow for the same interactions without taking any screen real-estate. And I have to say it quite consistent across the iOS apps I use.