Qt is LGPL like gtk.
Qt is FOSS, and the KDE Qt agreement make sure it will always be FOSS and can never be closed.
But yes, there is a CLA, and if you do not like, that is a valid point against Qt. But that is a licensing reason, not a technical one. Digia cannot dual license Qt to make money and would therefore not exist with the CLA so I do not mind it.
If you do not like it the solution is simple: do not write your software with Qt.