Animated GIF, despite having awful compression and terrible quality, is still more useful on the web than any other video format.
In 2013 people still routinely convert YouTube clips to GIF (producing postage-stamp-sized dithered-to-death desaturated blobs that use more bandwidth than a full HD video), because there's still no better way to share a short movie clip on the web.
Gifs are an abomination: they are heavy and the quality is, most of the time, terrible. However, their convenience is too good that people use them nonetheless.
The electrical cost of gifs must be gigantic.
Update 08 June 2018
There's hope. In a near future, and in other browsers than Safari, we will be able to use a video as an image to simulate a gif (ie., silence and autoplay). With perks of a video instead of an awful low-quality and heavy gif.