I am aware of the history of the cappa.
Our guardsmen do not wear helmets, swords, bearskins, red tunics or ride horses in battles these days. They do on ceremonial occasions and people flock to see them from all over the world.
Would you do away with the Queen's Birthday Parade or prefer the Swiss Guard in modern soldiers' uniforms with Ak 47s?
When one abandons one tradition all traditions become questionable.