Would people act differently in a setting in which the existence of gods, the afterlife...

This.
Unless the gods are actively intervening in the world to keep people behaving how they think they should.
And even then you should see a lit of people finding ways to rationalize weaseling around it, or just not bothering.

Only if they are publically known or using their true identities on earth. You're right about the WMDs though.

Greek gods, though. Imagine that you honestly believe that every time lightning strikes it's just Zeus having an anger fit. Also you believe that Zeus probably fucks your drinking buddy Philocrates, because well that's Zeus.

There's people who beleive the world is flat even tough there's hard evidence that its not.

So no. Besides its not like religious people don't actually believe in their gospel

>Atheists would still exist and be stubborn

I don’t think there’d be atheists. Or at least the people who atheists now wouldn’t be the kinds of atheists in such a scenario.

But what you might get are a group of people who for whatever region decide to abstain from worshipping the Gods. I mean, we know the sun is real, but there aren’t a lot of sun-worshippers knocking about. There’s a term for that kind of thing (acknowledging but not worshipping god) but I don’t know what it is.

that's the point, it's generic

unlike cyberpunk

Let's suppose is out of the question for whatever inane excuse.
Imagine all people, no matter how stupidly contrarian, are convinced without force or brainwash to see the truth: there are gods and magic and good and evil.
There are two main options.
-people who keep doing evil because of stupid egoistic impulse, same as the retard lighting his pants on fire because he believes he can easily slip through if things turn to the worse. And they will. And he probably won't.
-people who literally act like the gods command without the slightest hint of hope or bliss. They know that as a fact, as a rule, not as an act of good faith, they have to act like that to deserve the proper reward in the afterlife. Some might do out of sheer free will, but most will not. They'll just act good, but won't be.
Religions thrive on uncertainness and unprovability. If you prove godhood and objective good and evil, people won't just act good. They will just know different paths and some will still choose the wrong one.

You think the gods being physically observable would change there being atheists?

If anything it would make the ones who existed the most stubborn and conceited mortal beings to ever live.

>yeah yeah, i saw Gathros MYSELF last week..
>some "Star of the Dusk", he was barely even taller than my horse!
>you wanna spend your life bowing down to that purple fruitcake, thats your business. i've seen 'em and to be honest, i just ain't that impressed.

>Do you think people who believe in God don't really believe or something?

Most of them really, really don't. One need only to go to a funeral to see how hollow their belief is. If I told you your beloved father was leaving for several years to go to Paris France you would be bummed, but you would not mourn him. Yet if I tell he is going to Paradise, you would mourn him.

The people do not believe in Paradise like they do in Paris. They do not think of it as a place they could go, they do not imagine the heavens as having streets, walls, food, drink, inhabitants, culture, subculture, architecture, government, work, play, in short life.

The early Christians did, and they sang songs of triumph for their dead and insisted on saying 'they have just fallen asleep'. But the average pewpacker does not truly believe in these things in anything more then a strictly theoretical or hopeful manner.