There might be some confusion about Qt the runtime (ie: compiled binaries) and the Qt SDK for development. Last I remember (admitedly, >8 years ago) the Qt SDK certainly was a multigigabyte download.
In this case, you need the SDK to develop a UI with Qt, so I think the author's comparison is fair.
> Consider Qt Creator IDE which is quite minimalist, without Qt which it requires to run, requires over 200 MB Actual fact: 108.03 MiB
Probably depends on the platform, I wouldn't be surprised if it was > 200 MB on OS X. But either way, 100 vs 200, same order of magnitude