If you would have phrased this comment as a PSA (I have hearing loss and it's not great, please take care of your ears everyone!), it would have come better off. Your current comment just feels like it's critizing the author for a very minor joke.
On the theme of the article, sound is a great way to understand what is going on, and I really like how you've used it here. I think some people believe that hearing mainly applies to obvious sounds such as speech and music, but it is, as you demonstrate here, an excellent diagnostic tool. I've personally learned that all of the little sounds contribute significantly to ones mental map / model of the world to the extent that I'm prepared to believe that total deafness would be as devastating, in the long term, as total sight loss.
just keep rubbing it in
I don't usually agree with the pro-social-justice, everything-is-offensive PC crowd. But sometimes, a joke is in bad taste. It's not the end of the world, it's not a horrible joke the author should be ashamed of, it's not a huge deal, and "sorry, you're right, fixing" is a perfect response.
Your response however is full of severe insecurity. "Grow a backbone", as they say.
How can you tell? Why not give the benefit of the doubt that the apology was sincere and not grovelling?
As someone who needs to wear hearing aids, it's somewhat depressing to see hearing loss treated as a joke. Hearing all the little noises of the world as you interact with it is more precious than many people realise.