Not that I like the prequels all that much, but this isn't 1950 and you don't need a single protagonist. A New Hop is also a massive cliche of the stereotypical hero story that has been done to death a million times over in the thousands of years literature has existed. It's why that movie was panned when it came out.
There's no single protagonist in the LOTR movies either, and those are all excellent.
Story telling uses basic elements again and again. When those elements aren't used, the story has to be extremely compelling and interesting to keep the viewer engaged.
The plot and story telling are a mess in the prequels. And since Star Wars is just a basic hero's journey in space (GL confirms that) the absurd brokenness of the plot and characters in 1,2 and 3 kills the entire trilogy.