Likewise in war movies. Everything today's scriptwriters know of war, they picked up from watching Vietnam movies. That was an unpopular, hopeless conflict fought by draftees who often didn’t want to be there, so naturally the movies written by veterans often feature disenchanted, unruly, squabbling soldiers. But it makes no sense to apply the same dynamic to the troops at Dunkirk or advancing after D-Day – except that's the only way the writers have learned to imagine war.
Star Trek's famous "lack of conflict" is often mocked as naïve, not least by its current writers, but in fact it's the same dynamic as professional astronauts describe. They don't muck about the way George Clooney's character is shown doing in Gravity, nor snit at each other like rivals in a high school movie. When I worked in game development I used to encourage a team attitude where everyone is pulling together to face the common challenges. I called it "bridge of the Enterprise" culture, the very paradigm of grown-up, ego-free cooperation. It’s getting hard to remember now, but that’s what Star Trek once stood for.
Star Trek: TOS didn't lack for character conflict, of course. Not an episode passed without McCoy and Spock having a grumble about something. But I suspect what the producers of Star Trek: Discovery mean by conflict is to have characters constantly at loggerheads like the crew of the Prometheus. Presumably they’d interpret “bridge of the Enterprise” culture nowadays as all about recriminations, secret passions, grudges and shouting matches. But if the show is to make any kind of sense that could never happen; those characters wouldn't get into Starfleet in the first place.
More to the point (because credibility in SF and fantasy is so often taken to be a foolish goal) writing high school moodiness into all the scenes is the story equivalent of putting lens flare on everything. There are other ways to inject tension into a plot, other varieties of conflict than person to person, and other tones of conflict than the shout-n-sulk.
I don't want to get sidetracked into talking about The Rings of Power (which I haven't seen, nor the Peter Jackson movies either) but from the criticism it seems it's making exactly the same mistakes as those other shows and movies. Writers who only have a very limited range of character- and story-tropes not only know nothing but how to write "piss and vinegar" characters, they even think that's somehow innovative.
I'll leave the sign-off to Ursula K Le Guin. This is from her essay "From Elfland to Poughkeepsie", which is mostly about the jarring language used by bad writers, though that's part and parcel of the same problem:
"Tolkien writes a plain, clear English. Its outstanding virtue its flexibility, its variety. It ranges easily from the commonplace to the stately, and can slide into metrical poetry, as in the Tom Bombadil episode, without the careless reader's even noticing. Tolkien's vocabulary is not striking; he has no ichor; everything is direct, concrete, and simple. Now the kind of writing I am attacking [...] is also written in a plain and apparently direct prose. Does that make it equal to Tolkien's? Alas, no. It is a fake plainness. It is not really simple, but flat. It is not really clear, but inexact. Its directness is specious. Its sensory cues—extremely important in imaginative writing—are vague and generalized; the rocks, the wind, the trees are not there, are not felt; the scenery is cardboard, or plastic. The tone as a whole is profoundly inappropriate to the subject."
