[guessmyname]

> Why are QT and GTK not nearly as popular?

Because the people who are building and releasing these Electron apps are not interested to learn GTK/Qt; simple as that. Same reason why JavaScript is so "popular" because it's easy [1] to learn and — with the help of these other projects, Electron just being one of them — it becomes very easy to develop "cross-platform" applications.

Imagine being a 12 years old interested to become a desktop application developer, and then someone comes and gives you the option to spend several hours learning GTK/Qt with C++/Python, and then another person gives them the option to learn JavaScript (a language that is daily giving something to talk about) with Electron, what would be your choice?

[1] If you disregard all the ambiguity of the language.