The media functionality has improved dramatically the last few versions of WordPress, but consistently has been lacking one feature I know many people want (as listed here on this closed topic: https://wordpress.org/ideas/topic/media-library-folders).
I manage a magazine/news type site that currently has about 5000 images. I am pretty good at naming my images well, so the search feature is nice, but for instances when I just upload an image and it might be called: 98943img.jpg or something non-descriptive, it can be painful finding the image.
For smaller amounts of images, it might not be a requirement, but for a 1:1 analogy, could you imagine your Mac/Windows PC not supporting folders and just dumping all of your content into the one location?
I think folders are a great idea for WordPress to implement into the core or even a core supported separate plugin. I would gladly help with the development and implementation if it meant it would be added in.