I won't get into a long rant, but aside from on OSX, Slack and Atom are slow, resource hogging and unstable piles of crap. Atom couples that with bad architecture and engineering choice, but that's not Electron's fault.
(Also, your comparison with English is bad. English naturally evolved to the state it is in today. Javascript was designed from scratch, and it still manages to be awful. Also, sorry, Javascript isn't the most common language, thankfully.)