Android and iOS combined have about 96% market share, and neither of them work the way you describe. That doesn't necessarily mean either of them have the ideal design. But it does mean you have to give a lot more explanation before you use the word "should" so much.
It's true that with the current UI you can't change the ringtone volume while media is playing. But there's still no explanation here of why that would actually be a problem, or why it follows that the best possible solution to the problem would be for the sound indicator to only indicate ringtone volume. Did you consider any other possible solutions?
Android and iOS combined have about 96% market share, and neither of them work the way you describe. That doesn't necessarily mean either of them have the ideal design. But it does mean you have to give a lot more explanation before you use the word "should" so much.
It's true that with the current UI you can't change the ringtone volume while media is playing. But there's still no explanation here of why that would actually be a problem, or why it follows that the best possible solution to the problem would be for the sound indicator to only indicate ringtone volume. Did you consider any other possible solutions?