Riddle me this, why does stereo mixing done for foreign language versions sound much better? I suspect some combination of you know, actually bothering to mix d

Riddle me this, why does stereo mixing done for foreign language versions sound much better? I suspect some combination of you know, actually bothering to mix down to 2.0 rather than 5.1 and hoping for a miracle, or audio mixing overall simply being done in a way that emphasises dialogue over the music score or background sounds.