While I understand your concern, let's look at the other side of this medal. This is a general statement by the way. Destruction does not only mean you
delete pre-defined pathes in your game world. You can also use destructible objects to
create alternative or even completely new pathes. Do you agree?
As an example, look at the E3 teaser again. While obviously pre-rendered, maybe have a closer look at the gameplay elements shown there. If used correctly, environments can be used to create new ways or even paths to new areas you couldn't reach before. It is a teaser with exaggerated content, but the message for the game is shown right there. You can go in, having some fun and go BOOM! Or you can go in, remain having some fun, think about what you want to achieve - and then you go BOOM
Simple example. Imagine you see an orb - and with the existing environment there is no way you can reach that green little ball. So you have to begin to think about what you can do. Maybe the designer wants you to blow things up and find your own way here? In these kind of situations, the platforming aspect remains the same. We just went one step further in this very simple example. From here, you can transfer this example on much more complex gameplay situations - like in the teaser trailer, where you just made a BOOM for the truck that goes BOOM afterwards - resulting in an even bigger BOOM and a collapsing building.
Sometimes it's just fun to blow shit up. I think you agree on this
The challenge is to make the destructible environments also relevant to the gameplay.
Jumping from rooftop to rooftop while always searching these orbs, being this overpowered human thing. This is, in short, the Crackdown experience for me. As I stated earlier, this is also why I expected more "platforming" answers. But maybe this answer was too obvious and too connected with the franchise already. However, it's about adding another layer to that concept. Giving you a much more dynamic experience.