What do you think of this Persona 3 FES theory I came up with?

I'll try to keep this as brief and detailed as possible (character limit after all), my theory regards the Final Boss of the Answer, and not to mention some stuff from P4 so, SPOILERS ABOUND YO.

Now then to start me off I will say, what exactly WAS Erebus the final boss for the Answer? The game tells us this: it is a manifestation of man-kind's wish to die, but all in all, that doesn't say much does it? that is the equivalent of saying that it is an extremely powerful shadow, yet doesn't Fuuka (or someone else I forget) say that it ISN'T a shadow? (note I won't get on that point for a bit of time so do try and remember that)

In Persona 4 there are 2 bosses with the title of Sagiri, which Izanami states are a part of herself she broke off to "grant the wishes of mankind" now then also remember that little bit of info as well.

Remember when the team first learned about Nyx? Didn't Ryoji refer to her/it as "the Maternal Being"? Also wasn't Nyx supposed to essentially "meet up" with Erebus in order to bring humanity the "death" they "wanted"? WHAT IF, Erebus is actually some sort of Fraternal Being?

Now then before I brought up the Sagiri from P4, and for good reason, because this is where they involved, WHAT IF, like with the Sagiri, there is some even HIGHER being who created Nyx and Erebus for a similar reason to Izanami creating the Sagiri? WHAT IF, this higher being knew that humanity might end up "wanting" to die, so it created Nyx and Erebus (or at least some sort of base to bring of all of humanity's dark wishes together) just in-case that should come about?

Remember at the end of Persona 4 Arena where some sort of entity was revealed wanting to collect powerful shadows? WHAT IF, this entity is in-fact the higher being who created Nyx and Erebus trying a different method to end humanity because his old one was foiled by the P3 Protagonist?

now then back to Fuuka saying Erebus wasn't a shadow, were the Sagiri shadows? I don't think they were (ok I lied just Ameno-Sagiri, the one that comes out of Adachi, is the one who isn't as Rise stated that Kunino, the one that came out of Namatame, was formed due to a large was of shadows and it displayed too many things in common to it's host, unlike Ameno which had a unique personality and will) plus, Nyx wasn't called a shadow either, right? So if they ("they" referring to Nyx and Erebus again) created to bring about the same end by the same entity, why make them separate types of beings?

Ahem, welp that is all I got, also ignore the part where I go into about how Erebus isn't a shadow if you want, I am not as confident about that bit.

Like I said in the title, this is a THEORY, a FAN-MADE theory, it is in no way cannon and nor should you think it is unless revealed otherwise.