I notice visitors from countries with the highest online presence click far less compared to visitors in countries where 24 hr internet is emerging. I created my own test "ads" so i know they see the same thing. The difference in CTR is huge.
Occasionally ask people in my area if they click ads and the answer is usually a straight No. "Just ignore these ads" or "hardly see them".
Always sort of expected people to click more on image ads, but it's text ads that do best.