At this point the only OS with a consistent look and feel at all is Mac. For the other OSes, I don't even know what a "native" look and feel would be. And most apps have their own branding and style they want to tout anyway. So I don't think "apps should look native" is the leading reason to not use Electron.

For me, the leading reason to use Electron is the fact that I already have a browser running so why not just use that to render your webpage... Make it a PWA if you want it in its own window.