Ask HN: On which platform Electron based apps look best?
This is a really crappy Ask HN.
OP, you can find out yourself by just using a Electron app on the OS:es you are interested in. It should take you 5 minutes tops.
On the other hand, you should realize the Chrome render engine is used in Electron and you probably already have used Chrome on the OS:es you are interested in, thus answering your own question.