Where did the universe come from? Atheistic origin science has no answer.

[Sword of Christ]

So, since you already believe in eternal things that don't need a cause, what's your justification for ignoring the idea that the universe itself might be such a thing

It would entirely lack a context for it's existence it would mean we're an accidental byproduct. Freewill, morality, good and evil would be all be fucked if that were true. I don't see any good reason why that ought to be true particularly as we know our own universe is finite and had a beginning/point of creation. If it was eternal in itself it could have just been eternal in itself so that suggests an eternal force, particularly when you take into account the balance of the natural order and the complex nature of life. Yes there was evolution but you can see that as a progression from simplicity to ever increasing level of sophistication resulting in humanity, or something like humanity ultimately. You don't have to take Genesis 100% literally it only has to be true in general.

, and attributing that eternalness solely to god? You must actually have a reason, right?

I'm not saying you can't have an eternal universe but I would object to it on good solid grounds. It isn't wishful thinking either as it makes more sense for the universe to have an eternal context and some kind of purpose in the way it was specifically formed that isn't beyond the bounds of reason at all.