An interesting situation. I didn't think game developers did that, I know in the past you could run most games without sound (for memory reasons back then, but still) I did have a few month period in the early 2000s when my sound card was on its way from an RMA and every game then ran without it.
Might check the Bethesda forums for a -nosound switch you can add to the executable or something. Just for accessibility I would think that would be a desired option. Been a while since I ran into a deaf gamer, but it has happened in a few MMOs.