I've noticed this nerf on projectiles as well, however I don't think it will destroy camping utterly. There will still be campy players, but camping probably won't be as effective. In Melee, you have the option to play campy (and some players do), however playing agressive can also be very rewarding (since a character transfers momentum to their jumps and thanks to wavedashing), especially if you catch someone in the middle of the animation to fire the projectile.''
The differnce between Melee and Brawl is that in Brawl it is waaaay more rewarding to play campy and next to impossible to play a proper agressive style, so Brawl became, and still is; campy.
We can only hope that Smash 4 leans towards more towards Melee than Brawl when it comes to different playstyles. By looks of it; it does. So that's a good thing!