One explanation could be the climate difference. Egypt has a very hot and dry climate compared to Greece. Egypt would have more than likely focused on getting resources to survive rather than recreational activities such as art as much which explains why they didn't imporove on it dramatically. This idea is also prevelant in the two golden ages of Egypt and Greece. In Egypt the golden age focused on lots of trade with other countries. While in Greece the golden age focused on cultural advancements in the arts and architecture.
As a musical style, psychedelic rock attempts to replicate the effects of and enhance the mind-altering experiences of hallucinogenic drugs, incorporating new electronic sound effects and recording effects, extended solos, and improvisation.
