Most of my laptops are 1366x768. In fact, in a recent KDE survey, the developers got extremely surprised about how prevalent low resolutions were (it was linked around a few months ago). All developers are out of touch a bit, however, let's not forget that this issue wouldn't exist if Linux users weren't allergic to anonymous data-sending with statistics like these. Yes, no one likes privacy invasion and telemetry, but statistics like these are needed by developers.
BTW, on Gnome you can use the ALT button to move windows around when they don't fit. Still annoying though. Mint has 2 such windows too (their login prefs, and their panel settings pref).
Edit: More info here https://blog.davidedmundson.co.uk/blog/metrics-in-kde-are-they-useful/