First off let me say I think the Beatles were an influential group. Each member was super-talented, so this isn't necessarily a diss on them. That being said I think they are grossly overrated.
The UK is a small pound. It is easier to be a music legend in the UK compared to an ocean like the United States. The Beach Boys came before the Beatles yet that group isn't considered in the same stratosphere as the Beatles.
When I think about who revolutionized rock & roll music, I really don't think of the Beatles. IMO Elvis Presley had a greater impact on music. So did Jimi Hendrix, Ray Charles, and Chuck Berry.
There is a movie coming out in June called Yesterday. It is about a struggling musician who is about to give up when all of a sudden there is a global blackout and when he wakes up, the Beatles never existed. He starts performing their biggest hits and becomes the most popular musician in the world.
Again, I think the Beatles music was good, even great, not god-like influential. Most young people don't even know who the Beatles were. For example, when Paul Mccartney did some collaborations with Kanye West, NONE of Kanye West's fans knew who Paul Mccartney was. They actually thought Kanye West discovered Mccartney, LOL. IMO more young people know Elvis, James Brown, Hendrix, Prince than the Beatles.
Elvis was a working musician for 4 years and a cash cow for the rest of his life. He recorded some of the worst music to ever chart. That includes "Barbie Girl" and the entirety of Dylan's "Self Portrait." He was in the right place at the right time, he had incredible charisma and the ability to make somebody else's material go from decent to spectacular. But Buddy Holly was ten times the musical talent Elvis was.
Calling the Beatles a two man show is ridiculous. Ringo was a really good drummer in his own right and they even included some of his songs on their albums even though he could only play and write in three chords (G, C and D to be specific). George was an elite guitar player and influenced the Beatles records spiritually and politically (Within You and Without You, Taxman). Revolver, Sgt. Pepper and the White Album are three of the greatest albums of all time. Before the Beatles, Herman's Hermits was the top UK band in the United States.
The Beach Boys? Pet Sounds is routinely ranked one of the top 5 albums ever made. They're legendary. They were on FULL HOUSE.
Chuck Berry would go along with Buddy Holly for me. One of the best ever. Huge influence on the Beatles, too. Hendrix (rather, the legend of Hendrix) is overrated in my opinion. A tremendous talent that was more culturally influential than musically. Led Zeppelin and Black Sabbath had more of a lasting influence on popular music than Hendrix. But they didn't die when they were 27. Simon and Garfunkel, Janis Joplin, Neil Young, Elvis Costello, the Cure, the Clash, Joy Division, and David Bowie can join that list. The Kinks, The Who, Cream, Abba, the Mamas and the Papas. And of course, Dylan. In my opinion, all more of a lasting influence than James Brown, Hendrix, Elvis and Prince.
The Evolution of rock and roll is interesting and subjective. What isn't subjective is whether or not young people have heard of the Beatles. They have. And they have, in large, never heard of James Brown and have never heard a Prince song or a Hendrix song except on a commercial. Even people my age (I'll pretend I'm still an even 30) would be hard pressed to name more than three Elvis songs. Hound Dog, Jailhouse Rock and Heartbreak Hotel. I don't think he wrote any of them.
Interesting fact: they're going to make an Elvis biopic about his relationship with Colonel Parker who Tom Hanks has signed on to play. Casting Elvis should be hilarious. A room full of impersonators. I'd give the role to James Franco myself.