I know nothing about how Electron renders GIFs, but can guarantee you that there's no world where 16x16 animation should take up 20% CPU. Suggesting that we should convert them to tiny videos is completely missing the point.
The problem is that in popular usage many GIFs are not 16x16. People are sharing high resolution GIFs that can weigh tens of MB, and rendering several of those at once (whether directly in Chrome or in Electron) is not a negligible amount of CPU. It shouldn't peg a core, of course, but it's definitely higher impact than videos of similar sizes, since video rendering is considerably more optimized for these cases than GIFs are.
