But Nintendo owns the IP. Nintendo also keeps renewing the trademark. Doesn't matter who developed it. Nintendo can ask whoever they want to make a new one. Microst owns Lost Odyssey even tho Mistwalke developed it. There is a lot of Treasure developed IPs SEGA owns. Just because a 3rd party develops a new IP does not mean that 3rd party will own it. It's not uncomon for the publisher to own the IP rights and in the case of Eternal Darkness. Nintendo owns it.
I suppose this is semantics. In my opinion, a game that is not developed by Nintendo and instead, simply contracted, isn't a Nintendo game. Even if Nintendo OWNS it legally, it's not a Nintendo game. I view it in the same way as I do other mediums. When Michael Jackson bought Beatles songs... were they Michael Jackson songs? No, they were Beatles songs etc.
So, when I think of "Nintendo games" to revive, I think of things like F-Zero or Retro/Rare IP that Nintendo helped develop.
By that logic, Nintendo doesn't own either Kirby, Fire Emblem, Pokemon, any Mario RPG ever (from the original to Paper Mario and the Mario and Luigi games) or any of the Donkey Kong platformers. Yet we all agree those are IP Nintendo has control over, may not be fully in some cases but Nintendo controls the IP and thus has majority say on whether or not the games come out.
But yeah, put me as another person saying Eternal Darkness, while I know they now have partial contro on Fatal Frame, a good Eternal Darkness franchise could straddle the line between horror and action tones similar to Castlevania in its prime which would add to Nintendo's available genres.