As I somehow got the song “Operator” by Jim Croce stuck in my head today, it occurred to me that people hardly ever have to speak to an operator to make a call anymore and haven’t for some time. This got me to thinking about other songs that are either techically or historically obsolete. One example is “Back in the U.S.S.R.” by the Beatles. I know there have to be lots of other examples of this. It doesn’t have to necessarily be the title that’s osbsolete, but a lyrical reference.
Memphis Tennessee by Johnny Rivers suffers from the same problem as your Croce song.
Since Paul McCartney is now aged 66, “When I’m sixty-four” is now over-due for revision.
The Beatles line “I am the Egg Man, They are the Egg Men” in I am the Walrus could mean anything - but literally the “egg men” that were around in Lennon’s youth are more or less extinct - but certainly obsolete
The Staler Brothers song “Don’t Wait on Me” has the line: “When the lights go on at Wrigley Field I’ll be comin’ home to you.”
I think I heard on the radio once an updated version with the line changed to “When they put a dome on Wrigley Field.”
“I Love Rock and Roll.” Specifically, “put another dime in the jukebox, baby.”
Similarly, Happy Together: “If I should call you up, invest a dime…”
Anything by “Reagan Youth.”
Blue Oyster Cult’s “Burning for You–”
Time to play b-sides
There’s a bunch of songs that reference dates as being in the future or present that are now past: 1984, 1999, 20th-Century Boy… I guess it’s still possible to be “Livin’ in the '80s,” but it means something different than it did then.
57 Channels (And Nothin’ On): Really, Bruce? Only 57?
Not too long ago, Morrissey released a song including the lyrics:
In America, The land of the free, they said
And of opportunity, In a just and a truthful way
But where the president, is never black, female or gay
And until that day
You’ve got nothing to say to me.
Not quite obsolete, but hopefully it will be soon.
Songs with train references are kind of a gray area, I’d say, because there’s still songs coming out with train references, and trains still exist, but the references tend to be of the anachronistic sort.
Oh man, please tell me McCain is a gay female!
Western Union by… some guy who… oh, I dunno, may show up to defend himself.
Fell like saving me the hassle and explaining this? Wiki is no help.
From what I understand, McCain is a black, lesbian, parapalegic jew. Don’t recall where I heard that so no cite. 
I believe the “egg men” were like milkmen except, of course, they delivered eggs door-to-door rather than dairy products. I’m also guessing this was something that was mostly limited to the UK.
No, we had an egg man in our neighborhood when I was 8 or so (I’m 54 now). And it wasn’t just eggs, a lot of things were sold like this, one guy had produce (veggies and the like) and then there was the Charles Chips man who had a regular route delivering potato chips. We didn’t have it in our neighborhood, but there was a scissors-sharpening guy who went around from door to door sharpening knives and scissors. (And I wasn’t in a particularly urban area, where I think this was even more common, but in a suburb.)
Sting’s “Russians” has got to be a head-scratcher for those too young to remember the Cold War.
In Sam Cooke’s Wonderful World, he says:
Don’t know much about geography
Don’t know much trigonometry
Don’t know much about algebra
Don’t know what a slide rule is for
I know a lot of people still remember using them, but you have to admit that not knowing what a slide rule is for is not that much of an example of ignorance anymore.
I haven’t seen aha around here in ages.