they have shown and talked about various ways of navigating through the map AND dealing with enemies.
Again, those are just things you *can* do. Everything you see is basically a glorified lab environment where they show off features of the engine in a controlled environment. Gameplay doesn't happen in a lab environment that looks like a level. Gameplay happens in an actual level.
This is an example of gameplay footage. Gordon Freeman isn't just going "ok, now I'm going to show you ways that sticky tape can be handy." When he does something, it looks like it's because he's trying to play the game - not simply because the demo agenda calls for showing off the neato physics at 1 minutes and 33 seconds.
But when Carnby shoots a light, it's not because that would help him gameplay-wise; it's merely because the interactive lighting effects are item #1 on the demo agenda. No other reason.
the very name itself kinda makes that obvious
The name doesn't tell me where you got the word "survive" from. I suspect you got it from "survival horror," the term Capcom used to brand their series of AitD ripoffs, and unconsciously mixed it up with "alone in the dark," giving the portmanteau "survive in the dark" which I'm pretty sure has never been known to be a type of game.