As someone who's a huge fan of FNaF and has wanted to see it come to the event for 10 years now, am I a little disappointed it's probably not coming? Yes, absolutely.
Does that mean the event is now gonna suck and all the IP houses are bad? Heck no! Silver Scream Queens for the Monsters will be very fun, A Quiet Place could potentially be one of the most interesting houses, Insidious might not be too relevant anymore, but the 2015 house was terrifying. And while I wasn't a fan of the 2019 Ghostbusters house (and really not much of a GB fan period), I don't think the event is gonna be absolutely terrible and doom and gloom now, before literally *anything* has even been officially announced!
Long and short of it is that it's speculation season, things can change at literally any second, but guess what? HHN is only 3 months away, and we're all still gonna have a fantastic time going back into the Fog, regardless of whether you think the IP lineup is lackluster or not (which is okay to think... when the IPs are actually announced!).
Besides, this doesn't mean FNaF is never coming. We still got two more movies on the way and potentially more, it always has a chance in the future.