Well, that's the beauty of the Plateau as a device, isn't it? By starting players in an open area, but telling them the drop will surely kill them, Nintendo ropes off a portion of the space to turn an open-world (ahem, open-air, sorry)and gives them a hugely beneficial toolset all at the same time: In order to get the device needed to help you descend, you must first get yourself equipped with bombs, magnesis, cryonis, and stasis. Only then are you given the opportunity to keep moving.
Here's the thing, though- do you think those are the only runes Link will get in the game? I don't, personally. While I don't think all 100 shrines will give Link new tools (in fact, I could see some of them actually limiting you to one or two types of runes), I do think there will be more runes to use, and that the "cycle" of conquering shrines to get a piece of very valuable equipment might be something Nintendo utilizes in Breath of the Wild. That's an extremely satisfying sort of loot cycle and I think it would be a great way to give players direction even when they aren't necessarily following the plot.