Are they any plans to replace existing gui/other third party libraries with QT? I feel it would make it a lot easier to maintain the code because quite a bit of LO code seems to be made from scratch even for basic things. I had a look at the crazy ideas wiki and the last comments seem to be two years ago, during which time QT has come a long way.
I am not aware of any plans to convert from the Visual Components Library (VCL) to natively using Qt. According to this question/answer about GUI toolkits, the current arrangement is in place to allow GTK+/Qt parity. With the current rise of Wayland and fall of Gnome taking place it is possible that this situation may change in the future.