Conversely, it might just speak to the different kinds of music we listen to. "Dynamic range" is a pretty big phrase you'll hear in the mixing industry, and Airpods effectively have no way to determine how loud your music is before sending an audible notification. If you're listening to a song that's mixed at -12dbLUFS on Spotify or Apple Music, the alert will play at the exact same volume as it would when you're watching a Netflix show mixed at -25dbLUFS. The difference in sound is, quite literally, an order of magnitude apart, and could quite easily account for having such a loud and annoying sound blowing up your ears and ruining your listening experience.