Aromantics exist so "everyone can relate" is bs, they must feel so awkward listening music lolol
I think it's because it's such a strong emotion, it can make or break you, literally...
Being in love... It's magical, the best feeling in the world! Hearing songs that describe how you feel can make you even happier, on top of the goddamn world! If you aren't dating your crush (yet) it could give you hope, you get lost in beautiful thoughts and fantasies about them, hearing those words.
Then again, when you get rejected by a crush or dumped/cheated on by your partner... Your whole world falls apart, can lead to depression... Hearing relatable songs can comfort you, yes, those famous singers felt that pain too.
Personally, I prefer more uplifting "move on" songs. Not "I'm gonna cry, I miss her sooo much" songs, but "Screw that bitch, I deserve better" songs