I will focus on ONE single shortcut in Dark Souls 1 just to show you how insane it is that this game exists like this.

The classic shortcut. The shorcut of all shortcuts. The shortcut to beat them all. The shortcuts that made shortcuts a word of significance in game design...the undead burg bridge shortcut.

IMMEDIATELY this shortcut is better than all of DS3's (even the one in the witch level where the devs just arbitrarily decided to not give you a bonfire the entire level except for the beginning probably because the game is so easy and straightforward it doesnt hurt, so the shortcut to the twin princes is actually a bit more than just useful, but only for point #2 we mentioned regarding zelda)
Because in DS1, especially in this stage of the game where you wont have a lot of humanities or even know about them. This shortcut connects you back to the bonfires which is your entire healing system that allows you to survive going on.

But thats just the first level. And it already has two layers of the shortcut being used more than once, and genuinely being meaningful in sustaining you (purpose beyond mere convenience, it functions essentially as another bonfire without being a bonfire so that it can still maintain the tension of bonfire to bonfire travels)
The second level is that this shortcut isnt just used frequently...but is also TWO way