There are some user-level differences between an animated image and a video, which haven't really been satisfactorily resolved since the abandonment of GIF-the-format. An animated image should pause when clicked, and start again on another click, with setting separate from video autoplay to control the default. It should not have visible controls of any sort, that's the whole interface. It should save and display on the computer/filesystem as an image, and degrade to the display frame when sent along a channel which supports images but not animated ones. It doesn't need sound, or CC, or subtitles. I should be able to add it to the photo roll on my phone if I want.

There are a lot of little considerations like this, and it would be well if the industry consolidated around an animated-image standard, one which was an image, and not a video embedded in a way which looks like an image.