Why can't I enable GPU assisted Validation and Debug Print validation features together?

[azure widget]

I get this validation error:
Validation Error: [ VUID-VkValidationFeaturesEXT-pEnabledValidationFeatures-02968 ] Object 0: VK_NULL_HANDLE, type = VK_OBJECT_TYPE_INSTANCE; | MessageID = 0x6e432c51 | If VK_VALIDATION_FEATURE_ENABLE_GPU_ASSISTED_EXT is in pEnabledValidationFeatures, VK_VALIDATION_FEATURE_ENABLE_DEBUG_PRINTF_EXT must not also be in pEnabledValidationFeatures. The Vulkan spec states: If the pEnabledValidationFeatures array contains VK_VALIDATION_FEATURE_ENABLE_DEBUG_PRINTF_EXT, then it must not contain VK_VALIDATION_FEATURE_ENABLE_GPU_ASSISTED_EXT (https://vulkan.lunarg.com/doc/view/1.3.231.1/windows/1.3-extensions/vkspec.html#VUID-VkValidationFeaturesEXT-pEnabledValidationFeatures-02968)
Does one supersede other?

[jolly swallow]

Spec says so

As for the why behind that why... Not sure, other than it would be horribly slow

Maybe because it would need to reserve too many descriptor sets