From QTBUG-128383.

ProceduralSkyTextureData is by design unsuitable for low-end hardware since the resulting Texture is used as the lightProbe in the SceneEnvironment. This triggers the expensive pre-processing of the light probe texture on the GPU. There is no way to do this offline, obviously, since the texture data is runtime generated.

To enable the dynamic sky use case for a wider range of target hardware, some alternatives are needed.