Introducing deities into a setting is a lot like introducing time travel. It's something you need to add a lot of hard rules or explanations for lest the entire power structure of the setting falls on it's face. In CoC, most the deities were already either fallen to corruption, killed, wholly indifferent to the state of things, or in Mareth's case, barely clinging onto sanity. This pretty well explains why they haven't done anything to the demons before the Champ showed up. They just didn't care or were quickly taken out.
I feel like CoC II's been written into a corner, the fact the game's development has shifted many times with things like Etheryn not being a "trap" anymore, Berwyn, and various other character being scrapped. And it feels like there's a lot of stuff just there left hanging without it ever being addressed (Characters like Sigrune, for example).
So when we get to the seven, there's a whole lot of different reasons given as to why they just didn't gank Kas the moment she stepped through the portal, or hell, even explode Tollus's balls once they learned he was planning on fucking with dimension portals. From, they're curious to see Kas' soul research
(Which makes no sense, they could just do it themselves. Just command their faithful to participate in some experiments.), to they were busy
(Lumia literally has her fat ass plopped on her throne, the fuck do you mean, busy? She teleported into the Winter City when Kas opened her portal, but when Tollus opened his, where was she!?)
I really think there's potential here with the seven and how they could affect things, but honestly, the revelation that they're wraiths sort of hurts them. Like... On one hand, it's an interesting concept that they're these eldritch monsters that grew a concious and became self-aware. But man... It's also lame that they're not the OGs. Instead it's like
"Ohhh, well, maybe the real seven exists wooooo spooky-ooky!" It cheapens things like Lumia being the goddess of fertility that can't get pregnant, Kitsune society's 12 den mothers being descended from OG Keros's concubines.
And before we all crack the ol' reliable "PoWeR FaNtASy!" joke, I really don't think that's the case here. I think Savin and co really didn't realize the implications of what they're writing. They probably were like,
"Whoa, wouldn't it be so deep if the gods weren't the real gods!?" "Whoa... Dude..."
Not realizing that by doing this route, players would want to explore it further. And not just cocktease comments where Keros and M*llach go,
"Oh, so you know the secret, hmm? What are you going to do about it? No one's going to believe you anyways ohohohohoho~" This really sort of overshadows the main plot in terms of importance.