I think it's possible that Kishimoto might reveal things in the future that he didn't want to talk about in his earlier interviews after the ending of the manga.
His latest interviews show him spilling drops from the truth behind making Hinata with Naruto, SS, The Last and some plot holes left in he story. There are authors who confess later on in their lives. That is if Kishimoto ever had interviews again in the future.
Is it true? Any latest interviews that negates the ending? I'm not sure and frankly, if there is such thing, I doubt old fans would really care.
Regardless, I think it will not be a smart move for Kishimoto to undo NH/SS. The damage has been done and it is impossible to bring back his loyal fans that brought large financial support to his work (i.e. fans who enjoy a good story telling, NS fans included).
Whatever he plan to do next, he should not belittle his remaining fans anymore (NH/SS --the minority who supports his work financially). Yes, he made absurd comments about NS fandom during the heyday of this manga ending. What he got afterwards (i.e. NS fans leaving him behind) is a consequence to his own action. However, it should just stop there.
If he ever work on Naruto again, he'd need to start from the beginning and gain the loyalty of his readers the same way he gain loyalty from NS fans in the past 15 years before the ending. I'm not sure how it'll work, so good luck to him (note: I sincerely mean it).
Original Naruto manga went through ups and downs in the past 15 years of its run in terms of story telling. There were some periods where the story quality stalled or declined, but Kishi was lucky there are loyal fans (NS fandom included) who support him financially as far as manga goes.
Look at Gaiden and where it stood. Look at Volume 1 of Boruto manga, and subsequently Volume 2 and 3.
If I'm the analyst at the production house, the moment I see key indicators went down after Volume 64 of the original run, I'd flag out immediately. Look at the historical figures before Volume 64 vs Volume 64 onward. The decline warrants serious evaluation in the way the story was being produced. The rest is history. They all learn the lessons in the hardest way possible (i.e. fans leaving the series and we don't know whether they've reached rock bottom). All thanks to choosing to the loud minority instead of being consistent with the established story structure.
http://namaenasuyou.tumblr.com/ || https://www.fanfiction.net/u/6308104/
"I'm sorry I didn't believe. But I'd given up believing in so much, until I met you. From the first day I saw you, you were everything I ever wanted to believe in. You can do this, Diana. I know you can...But I have to go."
"What? What are you saying?"
"It's okay, this is what I came here to do. I can save today, but you... you can save the world."