Old Malayalam songs are evergreen and wont get older by days. Even at present too there are so many fans for these old songs.
New songs becomes hit in a day or two and will become annoying within a week. But this is not the case of old malayalam songs.
The lyrics of such songs have perfect meaning and touches everyones heart. Comparing to that, most new generation songs have nonmeaningful lyrics and music.
The another phase of new music is remix songs. They will just add some more western instruments and will make good songs defaced.
We still remember good music and old malayalam songs of Vayalar, Devarajan and P. Bhaskaran as they are evergreen.