Apps built with front end web tech are nearly always heavier than their fully native counterparts, for one. It's nothing for an electron-based app to gobble up 150MB, 250MB, and higher amounts of memory while doing (in terms of resources actually required for the given task) nothing. A great comparison is Sublime Text, which takes up ~35MB of memory at cold start, even with a few plugins enabled. Compare this to VS Code or Atom, which take around 200MB right out of the box. That's downright comical, and I can't accept the "but resources are cheap" excuse. That mentality has been robbing users of the lightning-fast, ultra-silky experiences that are possible even on decade-old hardware for years now and it needs to stop.
Aside from that, non-native applications inevitably introduce accessibility issues and UX incongruencies with the rest of the system that are difficult if not impossible to resolve entirely. There's a huge trade off made when using web tech for desktop applications and developers would do well to deeply consider their choice of technologies before acting.
It's not just RAM, either. If you measure "energy usage" however your OS allows you to (powertop or OS X's Activity Monitor, etc), Electron-based apps are absolute battery killers.
You'll lose literally hours of battery life simply by running Atom instead of Sublime. It's absurd how little regard Electron devs are showing for end-user resources.
Aside from that, non-native applications inevitably introduce accessibility issues and UX incongruencies with the rest of the system that are difficult if not impossible to resolve entirely. There's a huge trade off made when using web tech for desktop applications and developers would do well to deeply consider their choice of technologies before acting.