Earth Music in the SARP

Would, say, a person enjoying listening to "Ode To Joy" be unacceptable? As in, threatening...I guess the canon-ness of the SARP setting?

Simplified: Is the mentioning of popular songs today in RP a bad thing?

I'd prefer to avoid that sort of thing, especially songs of today because they're copyrighted material Star Army has no rights to use.

However, modern genres of music are fair game, correct?

Correct.

Ode to joy is completely fair usage, it's over 200 years old. Not only that but there is nothing illegal about /mentioning/ songs. I could have Edtoto rocking out to Panzer Batallion by Sabaton, and just mildly change the name of the band, and make a Wiki Page that explains that "This band is the SARP Version of Sabaton, all songs are owned by Sabaton" Boom, copywrite issue solved. Hell, I could even link to their song on youtube. I just can't claim their song to be my own, or property of Sarp.