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

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

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

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

Why would Joseph Smith say that polygamy was God's law?

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.

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?

A belief in a god is not the problem.

Can I see some saggy tit pics and huge areolas pics?

THE BIBLE IS THE PROBLEM!

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

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

Why is the concept of pumping water uphill not commonly used as a source of electricity generation, similar to pumped-hydro systems?

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

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

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

This Google experimental app lets you run powerful AI models without Wi-Fi - Android Police

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