I still have to give FNaF its credit for having spawned NEW YT channels--the Theory / Lore / Horror game ARG Mystery Deep Dive channels.
Again. FNaF got the perfect storm. This time it's even MORE aware of the community's and particularly popular Theory personalities involvement in its success, and thus it, even more so than Amnesia, is making games *specifically* FOR said audience.
All of the subsequent FNaF titles have been *Theory Baits* and unashamedly so. Which means--and this is weird--most of my enjoyment from the FNaF franchise has actually NOT been from the games per se, but from watching and interacting with the FNaF theory community--which then introduced me to ARG in general, which now I'm a fan of.
As what it does to the *horror* genre, eh...horror has always been shifting considering the audience has changed a lot. Take Callisto Protocol. It's so firmly sticking to what it did before (Dead Space) in terms of scares, sound, timing, atmosphere, visuals...and was it *scary?* Well. Not really? Is it a horror game? Yes. Did it make the genre better? I don't think so.
Callisto Protocol is stuck in the Dead Space era. It kinda doesn't have a place in the post-FnaF audience.