Using Electron and not even making it truly multiplatform is, like, willfully getting the worst of all worlds.
It depends. On my machine with 8GB of RAM and an older processor, Electron apps suck the life out of it. My newer dual core with 16GB of RAM (ultrabook) and an NVME SSD handles them fine. I think most devs working with newer faster hardware get a bit desensitized when it comes to performance. Electron isn't necessarily a terrible thing, but I refuse to call it "the greatest thing" - there's still a lot more work to do, like have a single shared Electron process for all Electron apps.