Exporting your images in their original formats can be useful for a wide variety of scenarios, especially when working with high-quality photos in other apps.
The drag-and-drop method is faster, but the 'Export' menu gives you more choices. You can get the original file by dragging and dropping in conjunction with a keyboard modifier, or you can get the original by using the 'Export' menu. If you need the original full-resolution file or want to get the video that's attached to a Live Photo, there's a simple way to do it. In the export menu, you need to select either JPEG, TIFF, or PNG, and if you don't make any adjustments to the quality settings, it'll likely be compressed. When you export an image from the Photos app in macOS, you may not be getting the whole deal.