You may be underestimating Granny Gertrude's powers. She will change a setting in a menu you didn't even know existed. /s

In my opinion, most modern movies and the like sound perfectly fine, like you said, when in a theater setting. I have a pretty decent home audio setup, and I enjoy going out to the movies for ones that I think will be fun or interesting. I usually do not have much of a problem hearing dialogue (well, I'm hard at hearing, so at least not more issues than I have hearing real world dialogue) and the only times things seem uncomfortably loud is when it seems to be done artistically.

The problem comes from the fact that most people don't have a "theater setting" at home, and since media is premixed for theatre setups with no way to adjust it, you're left with the worst of both worlds. I think that, rather than passing the buck onto the inexperienced user who might not know how or want to fiddle with audio track settings, studios need to start taking people's actual equipment into consideration when putting out home releases. Most media players give you the option for surround and stereo, but that does not help when the original media file has bad audio mixing from the get-go. If the actual audio tracks were mixed for "theatre" and "home", I think we'd be in a much better place.