No, my appreciation of the song and it's writer remain unchanged. Many lyrics come from places that are very personal to the writer, but have a different meaning to the listener. If anything, I have a little more respect for Simon and his ability to find a creative place to work.
I feel like this song is about finding a place that you can think and be alone. If that is the bathroom for some people, so be it. Many homes don't have a lot of private space, and not all people have their own room or studio to be alone and work in.
I believe artists write songs in a way that leaves the lyrics up to interpretation. In this manner it reaches out to a wider audience because the listener hears something that is relatable to them, making them remember the song better. Song lyrics don't usually mean something specific or detailed. Often lyrics are just thrown together.
Songwriters often write lyrics that are very specific to them, but in a subjective way so that the listener can relate to it too. This song is no different. Music and lyrics are all about what it means to the individual. Finding out what capacity a writer created the song in shouldn't change what it means to you.