Of course Sane C++ Libraries targets a much much smaller functionality subset than Qt (that is a good library in many ways) and of course it has orders of magni

Of course Sane C++ Libraries targets a much much smaller functionality subset than Qt (that is a good library in many ways) and of course it has orders of magnitude less complexity. You can use Sane C++ Libraries adding a single file to your project for example. Also, Qt used to have an LGPL + Commercial licensing scheme (not sure how this has recently evolved), while this project just MIT.