Until we get confirmation that this 10 year anniversary game is actually canon, we can’t really put it as canon

Every official FNaF game that was released on all platforms, was featured on Steam, and got some promotional campaign (trailers, and this time even ARG), was (and still is) canon.

There is nothing suggesting that this game isn't canon, except bias against books being part of the game-timeline and this game being book adaptation.

So a game that was confirmed to be a 10 year anniversary game must be canon, and it’s not like anybody knows yet if it is or not canon, is they put it on spin offs before any confirmations

There is always a clear difference between fun spin-off and a canon game.

Spin-offs as Freddy in Space series and Security Breach: Fury's Rage are very, VERY different and clearly made just for fun. They do not try to tie into the canon games.

Into the Pit not only has a clear storyline connected with already established places, characters and events, with many references to canon games which weren't mentioned in the original story. Examples: poster of Toy Bonnie (Toys appeared only in games so far, none of the novels), Helpy and members of Trash and the Gang in a dumpster (also didn't appear in novels), and even poster of Fredbear from Security Breach. I could go on and on. The description literally states it will help us to solve secrets spanning decades. Why would this be stated if the game was non-canon. If it were non-canon, then the answers to those secrets would dubious at best, and would be on the same level as The Silver Eyes trilogy.

What if we first wait it to come out?

I think you are not understanding the fact that the game literally didn’t release yet and it can be another fnaf world situation where it has lore implications but is not fully canon, plus nobody knows the canonicoty since it hasn’t released yet, so they put itp in some temporary spot until they get confirmations

But I still don't see the point of not including it with others in there. With every other game it was different, they were considered canon, even Special Delivery.

Why did it change now? Because it's an anniverasry game? Because it's a book adaptation?

I still don't see why should it be separate, except bias against books being in the same timeline as games. So far, what was revealed of the game, doesn't contradict previously established lore, on the other hand, everything suggests it's part of the main games.

Every other game and book was also put into their respective sections before they released. In some cases, even before official logos, keyarts and covers were revealed.