Paranormal Activity was one of the worst horror franchises since Blair Witch, which makes sense since they're the same concept: Fake home footage portrayed as real, the only difference is Blair Witch got shunned when it was revealed it was a fraud while this movie gets a wave of support. It's sooooooooo boring the movie as a whole relies on the audience suspending their disbelief willingly rather than being able to drive it's audience there with it's story telling and visuals. I'll admit though when I saw the 1st one, there was one scene(looking back it's an incredibly stupid scene) that got me for a second to suspend my disbelief, it was when they put the powder on the floor at night and saw the foot prints appear, that got me for a second then I remembered this isn't an actual home footage movie it's just shot that way.
For me mockumentary style like this, Office, Blair Witch, Parks and Rec etc. only work when the character's really come across as the character's and not just actors. Trailer Park Boys is the best mockumentary at that, for years the guys only did interviews in character, it really seemed like that's who they were. Same with The Office, Jim/Dwight/Meredith/Michael they all feel really genuine.