It would be nice if users could copy a CMake include file into their project that provides newer CMake API for older Qt versions. Qt VS Tools provides a qt.cmake that gets includes after the find_package(Qt...) call:

if(QT_VERSION VERSION_LESS 6.3)
    macro(qt_standard_project_setup)
        set(CMAKE_AUTOMOC ON)
        set(CMAKE_AUTOUIC ON)
    endmacro()
endif()

if(QT_VERSION VERSION_LESS 6.0)
    macro(qt_add_executable name)
         if(ANDROID)
            add_library(name SHARED ${ARGN})
        else()
            add_executable(${ARGV})
        endif()
    endmacro()
endif()

Qt Creator and Visual Studio Code could also benefit from such a file that's pulled in from the newest known Qt version and updated in the user project (on request or with user confirmation).