Notice how the more they focused on Toby's appearance

The less they focused on Toby as a character and the story as a whole?

The previous movies had so much original and creative scares, like the kitchen scenes, dragging scenes, furniture levitating, physical manifestations of Toby's violence like bite marks, nothing that would cause emotional tension and drama and in turn ripping the families apart, and Toby's appearance was lacklustre to be honest, nothing truly terrifying and matching the Toby that haunted Kristi and Katie, even the audio used for him was just flat, he didn't resemble the Demonic imagery that was presented through the first movies like the Baphomet imagery in the books and the footprints in powder, even when Paranormal Activity first came out I always envisioned it through my imagination to look like something resembling a tall being with a goat head and 3 toes, you know, something that is actually scary? And they could of started with glimpses of him, in 2 and 1 we saw him as dark shadows on the walls, in 4 we saw child sized shadows, they could of built up to it and had him start off as a horned shadow but with more mass, and it eventually solidifies into what I just described, maybe even hear him utter human speech at the very end, would of been awesome.

We also clearly didn't need the spirit camera in the first place because we could already see him manifest into the physical world via shadowy figure, in the previous films.