I don’t think people are necessarily super concerned with a notch, but the Overall redesign and implementation of 5G should be reasons to upgrade. The whole package is different enough to cause a super cycle because it’s less iterative.The iPhone 6 was so successful because of pent up demand for a larger screen.
The iPhone 12 will be successful because of pent up demand for a notch less screen (or at least a much smaller one).
iPhone X year (with notch) marked the year of the most iPhone revenue ever, $166B...even more than iPhone 6...mostly because it was a huge redesign.