This is a real pet annoyance of mine, and I have seeing apologist posts on the internet about it.
If the actors cant enunciate properly except when they’re shouting, that’s not adding realism, they’re doing bad acting.
If the sound engineers can’t get a good audio balance for anything except the loudest moment in a film, that’s not a limitation of technology/sound physics, they’re bad at mixing.
If the director can’t keep all of this in check and make a film that people can actually enjoy, that’s not artistic choice, they’ve made a bad film.