[s73ver_]

"I'd love to learn other languages and stacks! It's just that, often, it isn't a worthy use of my time. All that time used into learning C++ and Qt would be better used in making and improving my software."

This line of thinking, that it's not worth your time to learn tools that would improve your software, and make it less resource intensive, is a large reason for that trope.

"Many are using web tecnologies because of the fads, and some out of lazyness, but many (i'd guess most) are doing it because it's worth it."

I can't agree with this, mainly because, it's not worth it. It doesn't improve the software in any way; if anything, it makes it worse.