No one invented religion - it evolved over a million years, early man created the concept of God to explain his world and his existence.

Who knows???
I still think groups would form religious or non religious ideals. We would still be evolving animals wanting security for our groups. They will get larger in numbers
as we have. It will still be an eat or be eaten world that drives the security issue...

We would be in the approximately same state.

Ther would be less people contracting the COVD-19 virus. That's fact.

Anthropologists have suggested this idea could be endemic to all forms of higher intelligence throughout the universe. An article in the Humanist "Atheism, meet existential Risk studies" March/April 2016, outlines that this is another hurdle intelligent life forms must transcend to get to a higher level.
The way wer are headed, with luck enough will survive to carry on a new level of appreciation of nature and true, dogme free, sustainability for ourselves and the rest of life.

well, you are serving somebody right now i guess, or at least so goes the informed opinion. So wadr i think your Q is moot

What if? First of all, no one invented religion. It developed from the understandably ignorant minds of curious humans seeking explanations and was codified by people first trying to organize for mutual benefit and then by power-seekers, not one conniving human whi said "hey, let's make a religion!" so there is no what if. But even if there was, how in the world could we even say what the world would be like now or even IF it would be here for us humans?

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