Happy Birthday, Pop Goes the Weasel, Auld Lang Syne, Here Comes the Bride are obviously here to stay. Lots of Christmas music has potential as well: Jingle Bells, and POSSIBLY Feliz Navidad by José Feliciano, as well as All I Want for Christmas is You by Mariah Carey.
But I also think Barbie Girl by Aqua has a decent chance of being practically universal. In that vein, maybe the Hampster Dance too, but idk. Dragostea Din Tei?
I think the real answer though is that most of the popular songs are probably ones that are connected to specific uses outside of the song itself. Pop Goes the Weasel is used in like, every pop-goes-the-weasel type toy, and even in movies when something scary is about to pop out at you. Happy Birthday is literally sung at every birthday. (That reminds me of For He’s a Jolly Good Fellow as well.) Auld Lang Syne is a popular New Years song across the world at this point. Here Comes the Bride at every wedding, etc. Maybe National Anthems will also hold the test of time, depending on if the nation lasts long enough and doesn’t change its anthem.
The point is, if it’s a practical and traditional tune it’s more likely to last, I think.
Oh. I forgot Reveille which is the military wake-up call bugle song lmao