In my experience using both for years, Gnome has always been more stable.
Multi-monitor, Hi-Dpi support, in particular, is properly broken in KDE (while it's only half broken on Gnome).
As for features, the titlebar integration used by a few applications (ala MacOS) is a nice touch.
Otherwise it's true that the KDE experience, especially around customization, seems more thought out. Gnome's UX is nonsensical in more than a few places. The problem with KDE has always been stability and reliability. Having to reboot your machine due to crashes even once a week is enough to justify putting up with Gnome's overall worst UX.
As for features, the titlebar integration used by a few applications (ala MacOS) is a nice touch.
Otherwise it's true that the KDE experience, especially around customization, seems more thought out. Gnome's UX is nonsensical in more than a few places. The problem with KDE has always been stability and reliability. Having to reboot your machine due to crashes even once a week is enough to justify putting up with Gnome's overall worst UX.