Yes, in 1985. But it was Sega that provided real competition and
created the console industry as we know it by introducing the Genesis.
Oh, please. I don't think I've ever seen this level of pro-Sega delusion before.
Various Nintendo employees of the era have stated that Nintendo basically had no intention of introducing a more powerful system while the NES continued to be the juggernaut it was, but the introduction and success of the Genesis began the inter-company race that continues to this day.
Again...please. Of course Nintendo wanted to sit on the NES as long as possible. But it was never a matter of if they'd release a follow-up product, but when. Even Nintendo isn't stupid enough to think that technology lasts forever.