Famitsu also confirms that Tai Yasue is co-directing Kingdom Hearts 3 (which is expected since it was confirmed to be the Osaka team). With both FFXV and KH3 ending up with co-directors, I guess the era of Nomura being the sole director of the "big" games he's in charge of is over. It makes sense though, as game development gets too large scale, having one person oversee everything can be detrimental to the production process.
I don't think him being the "sole director" of 2 AAA games at the same time ever happened.