+Andrea Pernici can't speak on behalf of the search team, but my speculation is that you'll find the same rules for desktop in the future too. This just happens to be a much more painful experience for users on mobile, hence the focus.
there are dedicated sites that turn youtube videos into gifs (imgur, gfycat) and then turn the gifs back into mp4/webm to run them smoothly inside browser. it's hilarious. i do wish g+ would start converting animated gifs to videos for better delivery over browser and app like facebook/twitter.