Hmm...perhaps the reason that Advanced Warfare created the system of fast-paced movement was to lessen the amount of camping? Obviously, it will always exist, but in the games before AW, it would be quite annoying when people would just stay inside a building with one/two entrances.
It's just an observation that I've seen. Especially since BO3 tends to have locations that can be entered from multiple different entrances.
There's a difference between "camping" and defensive gameplay, even though most people make no distinction between the two, and simply whine about "camping" any time someone plays a defensive style.
Just like playing an intelligent run and gun style is different from spazzing around the map with SMG's like most people do.
People SHOULD be able to lock down choke points and areas with snipers and LMG's. It's always been a part of CoD until recent games. Can't outshoot them? Too bad. In the past there were always ways to deal with them, but they took more tactics and skill.
Now the game wants to cut that out and make it as thoughtless as possible and gear the game towards people who want to flail around the map with little thought, and then complain about the "camper" who is playing an overwatch role in a building by the B flag on domination, who killed them. Why outshoot or outsmart them when they can simplify it by just being able to float into the window, and have a perk system/movement system, and map design that is geared more towards them?
As I said, these things, the movement system and others devolve the game more and more into one playstyle, when not everyone wants to play that way.