I think rather Qbs (the build system that was supposed to replace qmake) was deprecated, in favor of either cmake or qmake (both of which are still actively developed and supported).
Qbs is deprecated. Building with qmake is still supported for end users of the Qt framework. For building Qt itself, since Qt6, the build system was moved to CMake.
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Qt Creator has always been one of the nicer free C++ IDEs, and qmake one of the nicer build systems. Even if you're not doing Qt development at all.
Qt Creator is reasonably nice. I believe that qmake is deprecated now though in favour of CMake.
I think rather Qbs (the build system that was supposed to replace qmake) was deprecated, in favor of either cmake or qmake (both of which are still actively developed and supported).
Qbs is deprecated. Building with qmake is still supported for end users of the Qt framework. For building Qt itself, since Qt6, the build system was moved to CMake.