Simon & Garfunkel - So Long, Frank Lloyd Wright Lyrics Meaning
"So Long, Frank Lloyd Wright" is one of several songs on the "Bridge Over Troubled Water" album that deals with the gradual breakup of Simon & Garfunkel. By 1970, when they made that album, Paul Simon and Art Garfunkel weren't getting along, and Garfunkel was beginning to pursue other interests, like acting in movies.
Paul Simon could see that they were heading in different directions, and he wrote this song as a way of saying goodbye to Art Garfunkel. It helps if you know that Art Garfunkel was a math major who originally planned to become an architect, like Frank Lloyd Wright.
The song is saying, essentially, "Hey Art, remember when we were kids and we'd spend hours singing Everly Brothers* songs together, and learning to imitate their harmonies? Those were the good old days... but I guess it's over now."
That's probably why Simon decided to include a cover of the Everly Brothers' "Bye Bye Love" on the album.