Stop being so literal. No one said that walking on them would be new. The point was about the difference between an open walkway vs spaces that are obstructed or otherwise not as commonly traveled.
I shouldn't have to spell out that crowd movements (and level of attention from people) going through an open space are different than movement along a wall, corner, or around an obstruction.
When you put something along a wall... it differs from putting it across the middle of the path. People moving around obstructions pay more attention because they are navigating and expecting variation. Things along the wall or in corners do not get the same kind of traffic over them because they aren't in the general path of movement, or simply because they may be too close to the obstruction to actually be in the actual foot paths. Only so many people can fit in a physical space that is crowded by an obstruction like a wall.
People moving through a continuous open space get lulled into complacency and pay less attention because they are not expecting their footing to change. Add in crowds where you can't easily see what's in front of you, and people loose track of their footing and steps. It's why the rails in mainstreet are such a problem and why guests aren't simply 'paying more attention' where they step. It's a situation that is harbored because of the environment and conditions.... and when you unleash the masses... probabilities do their thing.
So it IS different. Do I think it's some huge risk? No. I'm just more facinated by Disney not just biting the bullet here and continuing on with the next phase of the change. Why go through this effort to make the paths traversable again... just get on with it already.