Lighter elements (like hydrogen and helium) have been present since the beginning of time, and we see them largely in stars undergoing fission and fusion processes.
It is THESE processes (combustion of hydrogen and helium in a star) that CREATE heavier elements.
This process takes time.
We can only get elements up through iron before we need suns to take over and start crafting heavier ones.
That is why we see predominantly helium and hydrogen... it takes a while to make the rest.