Ouch! I had never thought of that.
I would say wrong tool for the job.
I dislike web techs with a passion (but html and css), they ruined internet for me. By using them for GUI, you are just turning the GUI experience into the same misery that it is using modern websites.
In some years, with Wayland, or W follower, or the new Cambridge X, everyone will have to reprogramme all graphical applications.
Really, it makes really no purpose to code anything hard, taking a lot of time, free without being paid, if you are alone on a single project. Co-workers are important for moving to next cool, shining graphical library, maintaining it.
If made alone, it is better to leave graphical applications for google, mac, apple,.. big companies that have lot of people for a project, lot of money to rewrite and remake the wheel with new libraries all over again and again...
really maybe the good way to go is to learn C++ or C, and likely to learn termcap / ncurses.
It is not GUI but CLI, still beautiful...
here a rapid example...
mc, vim,... emacs,... there are many famous programmes still, but of courses, you need QT, GTK,.. for nice softwares and desktops!
But,... yeah, why not QT? it will be there still for some time, until a shinning graphical library becomes fashion, in, a la mode.
Anyhow, computer hardware is very good today, you can screw the memory usage.
Look Internet, you use it daily with your browser, so?
In Conclusion:
You really need CLI and GUI, both.