Electron maintainer here. Electron is performant if the app developer writes good code. It's slow if someone writes bad code. That's the same if you use Apple's native APIs.
The big advantage of Electron is that it takes so much less effort to write an application and bring it to all operating systems. Thus, we get applications that would not have been developed if Electron did not exist.
As a fellow Electron maintainer, I want to say that Felix is a great engineer and an incredibly kind person. He is not an evil mastermind as portrayed in the article. We should be thankful for his contributions to the world of computing.
The big advantage of Electron is that it takes so much less effort to write an application and bring it to all operating systems. Thus, we get applications that would not have been developed if Electron did not exist.