Oh, brinstar theme changed very much between Metroid and Super Metroid. All the songs (or at least most) got completely new tunes that still represented the style of the environment. And I actually prefer the super metroid tunes. The old ones are good, but when I think Norfair, I think Norfair - Ancient Ruins, and when I think Brinstar, the dicotomy of upper and lower come to mind. Very catchy stuff.
I for one was very startled by this source tune when I first heard it. I was like "wait, this is Metroid? It's so... light and fast paced." Then I explored that green area and decided that it gave a really good feel to Brinstar. Brinstar is not just all dangerous, eerie, and dark environments. You have harsh places like Norfair, dark places like Maridia, Lower Brinstar... But then you also have a lush, verdent, overgrown area. That being said, it's still a dangerous place. But again, what stood out to me was just how lush upper brinstar was (and it was a good break after struggling through the maze of Crateria the first time I played...)
8 Bit Instrumental really captured that vibe for me in this, so that was really cool. Lush rainforest from Brazill meets Brinstar's overgrowth area!