Most of it is usually just images. Sometimes designers release them as SVG, but the image is embedded into the file, sort of like a rar in a zip file. Modern d

Most of it is usually just images. Sometimes designers release them as SVG, but the image is embedded into the file, sort of like a rar in a zip file. Modern design doesn't really care for size either. There's a reason we did flat design in the past - we'd have fine control over how to stretch a button. Now we have things like glows, animations, 3D stuff, which doesn't compress well at all. As engineers, we've had to push against one glowing effect which add 2 MB. There's also SDKs for everything, and these SDKs tend to add 10-20 MB here and there.