Ask yourself why more people don't use Qt:
(1) With web technologies you can write once and run everywhere including mobile to some extent. Writing a UI multiple times is monumentally expensive. Even huge companies don't like to do this, let alone indie efforts and startups. If Slack with its billion dollars doesn't do it what does that say?
(2) The ecosystem is far more active. The web is the largest open source ecosystem in history. There is code to do literally everything and an embarrassment of riches when it comes to libraries, frameworks, connectors, etc.
(3) Qt isn't that much less bloated than Electron, especially when you start styling it and get dynamic.
(4) Long build times mean that I have to wait a lot longer between dev/test. UI development tends to be a whole lot of iterative hack-test-hack-test. With web tech it's literally edit-refresh, which is much faster than edit-make-wait-launch.
(5) To make Qt look good you have to start styling and using its weird surprisingly web-like stylesheets, which takes you out of pure native mode and into a hybrid rendering mode. At that point I'm halfway to browser rendering.
(6) If you code UIs with web tech you also get the web, meaning your app could be run remotely in a browser as well as locally. This is the networked app promise of X11, Citrix, etc., and you get it for free.
Electron is popular because it delivers a ton of value in terms of cross-platform compatibility, reduced effort, rapid development, consistency, and ecosystem. Performance and memory use problems can be fixed.
I have been watching this project:
https://github.com/andlabs/libui
It's a genuinely lightweight wrapper that looks really promising. Trouble is everyone I show it to says "ugly" as their first comment. Everyone wants styled apps today with polished UIs and that takes you down a path that looks increasingly like CSS whether you like it or not. I also have this strong feeling that if I wrote with it I'd be rewriting in 5 years after desktop UIs are abandoned in favor of 100% web technology everywhere. Of course web UIs shift a lot too. Maybe the fate with UIs is to rewrite every 5 years no matter what.