I'm not seeing an update to YouTube, and my YouTube app does not currently do this. Perhaps they're rolling it out slowly, but it seems almost self-defeating to me to do this. One of Android's main selling points is how customizable it is, and the way apps are easily able to hook into the OS.
Removing that ability from the YouTube app doesn't make a lot of sense.
edit: Just checked, I'm on the same version as the blog post lists -- 5.2.27.