Yes, there’s multiple posts about it on the forums and Reddit as well. Although it is older news. This happened back in mid-July. I made a post about it, as well as many others. People were recognizing his animations were SLIGHTLY slower, and that things like the shield+jump method no longer work.
Adapt and overcome. They definitely will not fix any of the slow reaction times Reinhardt has now. They’re very small, but they are recognizable after several games (when it happened).