It will depend what you are optimizing for. If it is file size, then procedural will be like 1000x better and smaller than images. If it is quality, then you can get more detail (for example, from noise) and more resolution from procedural than textures, though there are still limits. In terms of speed, I would say premade textures will still be faster. Because the texture rasterization is done in hardware, it is super fast and can handle high res textures and PBR materials and mip mapping interpolation, etc. with no problem. You can do this with procedural too (by baking to a texture) so I guess you can have the best of both worlds, but it is more work. Textures are faster and easier to create, so you optimize for the schedule and budget of your game. But they can be less flexible. It is not that one is better or worse, and it will depend on the aesthetic you are going for.
