In my opinion there are simply too many gods.
We haven’t even touched on the gods of other races other than of course Phaestus and Nét (Aodh’s boss)
However, more to the point, for the last several thousand years, the Etonians have been working on eliminating a lot of other human gods, e.g. the Nyjyr Ennead.
We also haven’t seen a lot of the gods that are native to Norelon, the Narveson. They never had a large presence on Earth. They were there at one point, but were wiped out.
On Astlan, some of those you mention are here in smaller groups, still. They are also around on other worlds in the localverse