Why does it matter so much to atheists that God doesn't exist?

IT does not matter, mainly because it does not exist.

Because these are not any gods rules we are talking about.

The people of the modern world have evolved past all of that nonsense.

AMD has limited Radeon RX 9060 XT 8GB sampling based on ‘regional market demand’ - VideoCardz.com

My problem is that people who try to shove their rules down everyone's throats - including by physical force - DO EXIST .

Notice that I said their rules, not any gods rules.

These are man made rules - made thousands of years ago for the use of the humans who lived thousands of years ago.

How effective will the Senate-passed bill, S. 4569, the Take It Down Act, which would criminalize the publication of non-consensual intimate imagery (NCII) be?

I am speaking to the US Bible thumpers here, of course ~ many of whom are flat-earthers who deny evolution and see scientists as evil people who are constantly trying, and succeeding, in disproving their beliefs one by one.

A belief in a god is not the problem.

And how do you deny hundreds of years of advancement in all fields of science?

Researchers are starting to untangle the links between cognitive processes, emotion regulation, and depression - PsyPost

THE BIBLE IS THE PROBLEM!

Those rules that you are trying to reinstate are rules made by men who didn't know anything about the earth, nor anything about all of the other inhabitants of it. How can you not see that?

And then use and ENJOY these fantastic scientific advancements every single day of your life?

3 hours of sleep and no fatigue? Scientists uncover the secret of natural short sleepers - Times of India

I do not personally care if you believe in a god or not.