I think the fact that more elements of LoZ are used even today is a testament to the influence it had on the Zelda series and video gaming as a whole.
Zelda 1 was a great adventure with several strange hidden things, heart containers, dungeons, keys, maps, everything the way we expect it. It feels and plays like, well, a Zelda game. It's a little bit plain and there's not much interaction, but it's pretty good for a 8-bit game.
Zelda 2 was hurt badly by it's poor translation given the importance of dialogue in an RPG-like game. But even putting that aside, it plays more like a fighting game or Castlevania than like a typical Zelda game.
ALttP clearly takes primarily after Zelda 1. So does LA. OoT was very innovative in its own right, but the core mechanics outside of the 3D and such still seem to come from ALttP. I think Nintendo took the series in that direction partly because they knew it made sense, and partly because they knew it was what the fans wanted. And it worked out quite well, so I'm inclined to believe they knew what they were doing.