FYI. After adding more debug output to the cmake_install.cmake file, I found:
cmake --build Build/build64/VS2022 --config "Release" --target install
sets BUILD_TYPE
and
cmake --install Build/build64/VS2022 --config "Release"
does not set BUILD_TYPE but passing in the command argument -DCMAKE_INSTALL_CONFIG_NAME
With this information I was able to hack together a workaround of
CMAKE_INSTALL_PATH=<path>/\${BUILD_TYPE}\${CMAKE_INSTALL_CONFIG_NAME}
that works for both install modes.
Still, this feels like it might be a defect.