Actors should never be whispering or mumbling for real. Even an actor pretending to be drunk should be able to clearly enunciate their words while still making themselves sound drunk. I'm sure modern actors can still do this, but they're being given bad direction.
I can't comment on the sequels.
Absurd.
But watching any US movie and I have to either turn on subtitles or blast it so loud that some action scene will probably crack speakers or the wall, since I hate getting lost in plot.
If they mixed it right, center speaker should be mainly dialogue.
And no, this is not a technical limitation: case in point, the new Star Trek shows. We've had three of them produced in parallel, sharing some sets and props, and they go full-spectrum - from "every scene is night scene" Picard, through "everything is underlit" Discovery, to "everything is bright well-lit all the time" Strange New Worlds.
The only reasoning I can think of for making what's clearly an artistic choice is that maaaybe it looks better on actual TV. I wouldn't know, who owns a TV these days anyway? But I got one clue - rewatching parts of last season of Picard on a hotel TV, I was suddenly able to make out colors and shapes that I couldn't on a computer screen.
I am going to guess a majority of people in the US live in a residence that contains a TV, probably even a large TV.
I must be odd because I have 6 of them: family room, office, master bedroom, both kids’ bedrooms, and back patio.