A long time ago we didn't have the scientific abilities we have now.<quoted text>
"Most regular people on earth and most scientists believe the world/universe to be Billions of years old."
A long long time ago people believed the earth was the center of the universe.
So all this means is a lot if people are wrong.
A long time ago most Western civilizations were controlled by religions and they kind of put a damper on some kinds of knowledge.
The earth being the center of the universe was a myth promoted by the church because God loved us and we were 'special'
Of course we now know that that wasn't the case at all.