Maybe you listen to music while browsing the web, but what if the thing you listened to wasn’t merely music, but rather gave you the vital context you needed in order to understand what it is you’re browsing? This is key to understand why offering independent volume control to media with a play button is so significant.
When volume control is only available via the system settings, it creates significant barriers for screen reader users, given whatever media is playing then has to compete with the screen reader.
Additionally, I believe that independent volume control benefits everyone’s user experience, not just those using screen readers. How often have you had to mute your system audio because of some unknown tab began playing audio? This also highlights another issue of audio control: audio that plays automatically. In general, people find this obnoxious, but imagine being a person using a screen reader. The audio you hear is not only helping you navigate the content, but then automatically-playing audio starts, potentially making it impossible to know how to stop it. The very thing that gives you the ability to stop the sound is also the prime offender to your ability to navigate the page. 😳
In conclusion, I am realizing that accessibility and great user experience are things that go hand-in-hand. We can improve access to people with disabilities, while also making the web a better experience for everyone.