Did Sparta become the most powerful city state of golden age?

No, Athens became the most powerful city-state of the Golden Age. While Sparta was a formidable military force, focusing primarily on militarism and warfare training of its citizens, its dominance was largely restricted to the Peloponnesus region of Greece. On the other hand, Athens underwent a cultural, intellectual, and political golden age, attracting renowned thinkers, artists, and philosophers to its city and expanding its influence over much of the Greek world, both culturally and economically.