Certain groups are asking that video creators add closed captions to videos and it would be a good idea to take their advice. Adding captions is not that hard; all you need to do is transcribe the video and then add the transcript to the video; just make sure that the captioning reasonably matches the spoken word and you should be good.

For what should be part of the process anyway, you do more than make someone happy: You potentially increase your audience as those with hearing disabilities can now enjoy your videos; they can now watch the video and get more out of it than before. Also, having the transcript and posting it gives you more relevancy in search engines, as they have more on you to track. Those are healthy benefits from something you should be doing anyway, giving you added bonus for effort.