On OSX there is a noticeable difference in performance of video playback in Safari and Chrome, and I'm pretty sure it's all down to hardware accelerated decoding.
They've got hardware accelerated CSS3 working right in the latest versions, but VP8/VP9 won't work. The explanation is that Safari doesn't support VP8/VP9, so a fallback to h264 happens and the hardware accelerates that properly.
But I can't really blame Chrome for something that is out of their control. I recommend checking out gfx.io, that way you know what gpu is active. You can also lock it to internal only if you don't use external displays or anything that really requires the discrete gpu.