Plenty of category leading applications like Discord, VSCode, Slack, Figma, etc. use it quite successfully.
Are there QT or GTK competitors crushing them?
I always hear how terrible electron apps are, but the companies picking electron seem to get traction QT or other apps don't and seem to have a good cross platform story as well.
One that comes to mind that I use daily and noticed only recently that it was implemented in Qt is the telegram desktop app.
Companies aren't picking Electron due to inherent shortcomings in other platforms, they're picking it because it's easier (and cheaper) to find JavaScript devs who can get up to speed with it quickly.
Your comment applies to Teams and I’m sure other electron apps. But the sweeping generalization that electron apps have terrible user experiences is pretty obviously incorrect.
And most of the world is like that, very few of us (speaking globally) have $2k to drop on a new supercomputer every few years to run our chat applications.
It's also the option which gives your users by far the worst experience. Not worth it at all, imo.