I had a fun time with this once. The Jetbrains Toolbox app is written using Qt and is 150mb. I opend the .app package on mac, deleted the frameworks directory, and symlinked it to my system's Qt install.
They seem to build it against a reasonable version of Qt, I haven't updated it in a while (because it's just a launcher), and when I do I'll just re-symlink against whatever Qt is currently installed (which I do keep updated)
I understand your argument, but in this particular case things aren't volatile enough that it causes any problems, and if it does it's just as easy to solve.
It's now 6mb.