I watch movies with subtitles or CC all the time now, if I have the option. I'm not going deaf. Even with decent hearing acuity, I still miss a lot of what's happening, misunderstand a word or a phrase, miss completely what someone on the other end of a phone conversation is saying. Movies have such a wide audio dynamic range now that to hear whispers, you need to put your plaster and neighbors' good will in peril during action scenes. Also, you often get details you don't get any other way. One example is the name and performer of a background song.
On the down side, getting blurbs like BIRDS CHIRP is bloody annoying.