The correct answer to this open question is the following.
I do not agree with what John Green said.
John Green stated that it might have been better if the Persians beat the Greeks. His arguments were that the Persian life was not bad. Persians ruled prosperous cities. And he comments that life was not easy in ancient Greece if you were a woman or a slave.
Of course, Greece was not perfect and had many issues. But the Persia Empire also had its many issues too.
I think it was good that Greece won the Persian Wars. The Greek victory established a foundation of a classical time in which Greece "exported" the idea of democracy to other states, as well as the philosophical ideas of great thinkers of Athens. Arts, literature, sculpture, and architecture were other important Greek influences that transcended the test of time.