If you make a movie you make it with multiple audio tracks (lines), often there are dozens of lines for cinemas and more for IMAX. If you mix all those lines together, e.g. to 5.1 for home cinema you’ll lose dynamic range. Now if you mix it into 2 lines (stereo) this means you basically have everything (explosion, whispers) on the same two lines for left and right and that’s why you either need at least a front speaker for dialogue (so only effects are muddy but voices are clear) or bear with it.
Or studios could go back to properly mixing their audio when making versions for home setups
They do for 5.1, which is a pretty common home setup, even 3.0 or 3.1 works quite okay with it. How many people do actually watch movies with a stereo setup nowadays?
Anyone with a perfectly good tv that doesnt need a sound system.