He didn't wait so long. We took too long. Science has always been there. Timing is the most important thing.
There is a time for everything. Science and the Bible work quite well together. There's plenty of science in the bible.
For Example:
Genesis 1:1 begins "In the beginning" In these three simple words we already have a basic principle of physics. "In the beginning " is a statement of time. In fact this is a statement of the beginning of time. God is outside of time, but in creating the original material out of which He formed the earth, God also created time. Modern physics describes time as a function of matter. In fact, the atomic structure of matter seems to hold the key to the movement of time itself. Scripture states this essential principle when it points out that time and matter were created simultaneously. It only took modern science 6,000 years to catch up with the Bible.
Genesis 1:1 continues with "God created the heavens and the Earth." This is the only logical scientific explanation for the origin of matter. There is no naturalistic explanation for the origin of matter! Some evolutionists theorize that matter has always existed. But if this were true, we would not be here today. If matter always existed, even evolutionists must admit that the universe would be nothing but a weak, homogeneous field of energy today, according to the Second Law of Thermodynamics. The Big Bang theory does not present a naturalistic explanation for the universe.