The soundtrack is what sells GTA as an authentic, living, breathing open world. Ask anybody in this thread their standout moment of a GTA game, chances are it'll be a song playing on the radio while on a mission or just mucking about in the world.
Music is a powerful tool that can set the tone in a medium. Emotion, atmosphere, suspense, enjoyment, even character. Almost every song in Vice City/San Andreas feels right in the world without feeling out of place. Just listening to a mismatch of songs externally misses the point.
Also, remember that R*/T2 REMOVED the originals from digital storefronts. Now in today's digital centric world, it'll be harder to relive or experience those titles in their original glory. You're basically saying it's okay to re-release medias in a neutered experience because it's easier.