I guess that's my point - the author is already using Qt which has so much included, but are still including two large header files in the project just to output a ~12 line XML snippet
Qt is terrible. Since a couple of years they want a login just to download the code required for a build and I really have zero desire to get a bunch of marketeers that are wondering if I'm ripe for the plucking yet just because I've decided to fix some bugs in open source code.
IMO Qt is amazing. No login is technically required to download anything, especially code.
The official SDK installer GUI does require a login, but you don't have to use it in order to download or use Qt at all.
Not only can you download all the individual components that the GUI fetches via download.qt.io yourself, there's also third-party installers like aqtinstall, as well as many different OS package managers that provide Qt binaries.