It's true that much popular music is heavily compressed, but you normally wouldn't encounter two differently-compressed masters of the same song. Two exceptions would be radio (some stations used to apply their own compression, and perhaps they still do) and some high-quality releases aimed at audiophiles that are produced from a less-compressed master. I wouldn't think that streaming services like Spotify would re-compress songs.
I was a bit imprecise, but the "high-quality releases aimed at audiophiles" is essentially what I was referring to. The record stores are full of remastered vinyl editions.
