It usually also prints something like “Reason given by package: HERE-GOES-SOME-REASONING”, but there is none of that on your screenshot (could be that it is not the full output there).
Perhaps you could try to surround find_package() with a debug helper:
set(CMAKE_FIND_DEBUG_MODE 1)
find_package(Qt6 COMPONENTS Core Gui Widgets REQUIRED)
set(CMAKE_FIND_DEBUG_MODE 0)
and check the paths it will print out.
It also appears that you are using CMake 3.16, so I would perhaps try with a newer version, just in case.
And you still haven’t shared what configuration arguments/options are set for CMake to configure your project.
Not to mention that minimal version of a project, which one could use to try to reproduce your problem.