It's not just lossy compression you lose things like layers and stuff when you flatten the file to a bitmap. In the general sense this is the correct behaviour

It's not just lossy compression you lose things like layers and stuff when you flatten the file to a bitmap. In the general sense this is the correct behaviour but in the specific instance of doing simple bitmap manipulation like cropping "export as save" is expected and since thats the most common use case for many people it's probably frustrating. To be perfectly honest people using gimp for image cropping should use something else, gimp gui is clunky, it starts slowly and there is no benefit.