I think the audio quality has definitely improved. It's easier to access quality audio files from various devices, so it really boosts the listening experience. The downside is more about piracy, but that's something we can't really help.
The quality has definitely improved over time and one can just imagine how the situation will be like 10 years from now. Just like Yurimi has mentioned, piracy seems like that catastrophe that never goes away.
Personally, I would vote it has remained the same. Although I agree that the sound quality has improved, the durability of some of these items has definitely deteriorated. And here I'm speaking about popular brands.