I remember them mentioning that the larger reason for the delay was that it 'just wasn't fun,' but nothing shown here is really doing it for me. I feel like they've spent a lot of time repeatedly talking about the mechanics in a very broad sense, which is kind of worrying. Yes, you can hack people. Cool. So what? What does that mean for anything you do, why would you want to do it?
Outside a few particular cases (like the NPCs shown doing things in their private lives) I have reservations with what makes hacking particularly fun or interesting. You can pop up a road barrier a million times (like they've shown) but if that's all there is to it I'm not sure how far that can get you without losing novelty pretty quick.
edit; I'm not writing the game off completely, I'm just not sure what they want me to think of hacking when they're touting it as the huge core mechanic but then show the same 3 shallow uses in every bit of media.