Desktop processors generally have much higher single threaded performance. Thus apps can more often afford to take a performance hit on desktop than on mobile.
Electron happens to cross the threshold for sensitive users like you and me, but for a large number of users it seems the step in performance from mobile to desktop is enough to buy you the "Electron/PhoneGap/Cordova abstraction" (seeing as how there are popular Electron apps but few for PhoneGap/Cordova).