I think Electron is popular because you can hire web devs to make a desktop product. With JS you can write code that runs on your server (NodeJS) desktop (Electron), browser and mobile app (Cordova). It's not a great experience but it is good for rapid development, easier hiring of skills (just need some web devs!) and the code reuse might be helpful for bug reduction.
Bloated, yes. Slow, no. You start at a not so low binary size and memory footprint, but that's it. VS Code is an awesome IDE built on electron and it's really snappy.
