I wonder if the goal of bright, flashy uniforms was not the psychological effect that it has both on enemy and friends.
There's a long history of armies going into battle bedecked in attire calculated to test the enemy's resolve and bolster their own. Skyclad Celtic warriors and extravagantly feathered Eagle Warriors. Spartans with red chitons and Samurai with monstrous faceplates. My favourite example is the Parthian geneal Surena's flamboyant manoeuver at the Battle of Carrhae (in 53 BC):
The Parthians went to great lengths to intimidate the Romans. Firstly, they beat a great number of hollow drums and the Roman troops were unsettled by the loud and cacophonous noise. Surena then ordered his cataphracts to cover their armour in cloths and advance. When they were within sight of the Romans, they simultaneously dropped the cloths and revealed their shining armour. The sight was designed to intimidate the Romans.[24]
There's a long history of armies going into battle bedecked in attire calculated to test the enemy's resolve and bolster their own. Skyclad Celtic warriors and extravagantly feathered Eagle Warriors. Spartans with red chitons and Samurai with monstrous faceplates. My favourite example is the Parthian geneal Surena's flamboyant manoeuver at the Battle of Carrhae (in 53 BC):
The Parthians went to great lengths to intimidate the Romans. Firstly, they beat a great number of hollow drums and the Roman troops were unsettled by the loud and cacophonous noise. Surena then ordered his cataphracts to cover their armour in cloths and advance. When they were within sight of the Romans, they simultaneously dropped the cloths and revealed their shining armour. The sight was designed to intimidate the Romans.[24]
https://en.wikipedia.org/wiki/Battle_of_Carrhae#Battle