No, because he stated in this very interview that each trilogy would be separated by a generation. While that goes against what Gary Kurtz says, it also goes against what you're claiming. He also says in this interview that "Revenge of the Jedi" would conclude the Luke/Vader storyarc. So, yeah, maybe there were plans to have the original Star Wars storyline continue for another trilogy. Who knows? But this is proof right here that another trilogy, completely set apart from the current trilogy, did exist in Lucas's mind at some point. There's no defense against that.