Feels like a false argument. IMHO both are of value/importance, depending on the circumstances. In concert performance is more important, clearly. But in a session it would depend on the participants' interests - do they want to be entertained or do they want to learn about the song's history and background (or both)?

For traditional songs, background is part of their appeal, for myself. For contemporary songs politeness dictates that the performer attributes the song to its creator, at least. And let's face it, if one has bothered to search the internet or transcribe the lyrics in order to learn them, the author's name is pretty easy to find out these days.

But in any case, it's not an either/or - both are important. It's not as if one has to "sacrifice" one in the interests of the other, in any way.