It's a DONTNOD adventure game. That's the game.
In the first 20 minutes of Life is Strange you have a vision of a tornado heading toward Arcadia Bay, you're introduced to strange new time powers, someone gets shot and you save them using said powers. The first big choice is whether or not to report a shooting, pretty tense.
The first 20 minutes of Tell Me Why is you going through the respective twins' rooms learning little tidbits about their personal lives then dicking around on a boat. The first big choice is whether or not you accept a ring from a character you've never seen.
Now, personally, I like Tell Me Why and I like it's slower and more grounded opening just fine. But it's definitely fair to say that it's a slow start, even by the standards of a DONTNOD adventure game.