Same reason a book might spend two pages describing a lazy dog laying on a porch swatting flies with his tail, instead of cutting straight to who said/did what.
But what I'm trying to say is there are other tools in the toolbox now - I haven't heard anyone say that Everything Everywhere All At Once was bad, it's a great movie, absolutely full of deliberately chosen mood, and it never has to resort to extremely long shots that take the wind out of the story's sails.
I can think of a lot of older movies I'd not touch the pacing on. I don't think it'd improve the film. Then again, I admit I've bounced off a couple because of extremely-flat cinematography and slow-as-molasses pacing (the original Oceans Eleven comes to mind—I don't drop many movies that I start, but I'm not sure I even made it to the 20 minute mark on that one).
Maybe I'm misjudging what you mean by "old"—I'd kinda assumed you meant "before digital editing", say, 80s and earlier. I don't think films from the '70s tend to feel terribly different from modern ones (we've developed new and more-chaotic ways to assemble very bad action scenes, but that aside, not much different) for example, but would grant that it's probably possible to divide cinema into silent/middle/modern period as far as the feel or what's asked of the viewer, and that the former two do feel pretty different from modern films—but I'd say we were already transitioning out of "middle" and into "modern" in the '60s, so you've got to go pretty old to get into what I'd judge to be notably different.
Now, film films do tend to look very different from modern movies, even as recently as the 90s, but that's because easy digital color grading hadn't ruined the artform yet. :-)
Some movies were just never very good in the first place, I'd put the original Oceans Eleven in that category. On the other hand, compare the original The Italian Job to the remake. The remake has faster 'modern' editing but it's definitely a much worse movie than the (excellent) original.
Isn't that true of all movies?
I understand what you're saying - choices make it either loved or hated, but most movies don't have choices that split people that extremely.
Also, keep in mind survivorship bias - we largely ONLY think of the great movies from the 50's and 60's but have plenty of bad examples of modern cinema to easily draw from.
The passage of time doesn't play a role, because even though individual directors/actors get more experience with age, they also age out of the industry and get replaced with new guys. And besides, it is very often the case that movies get worse as a director ages. Compare The Godfather to anything Francis Ford Coppola has made in the past 30 years. Or Michael Mann's Thief and Manhunter to anything he's done in the past 20. Or Ridley Scott's filmography. There are many examples like this; experience counts for something but old men often lose their edge.
https://towardsdatascience.com/are-new-movies-longer-than-th...
But here again we're looking at Marvel movies and saying that's the entirety of what's being offered in cinema's these days. It's not, but it feels like it.
But there is no general relationship, direct or inverse, between the length of a movie and the quality of a movie. Some movies should be short and some movies should be long. It really depends on the movie in question.
Sometimes those scenes are fat. Poorly made movies are certainly not just a modern phenomenon.
But sometimes it's critical that those scenes are as they are.
Throughout this discussion I've realized that this whole conversation is fraught with survivorship bias - we imagine generic marvel movies or the fast and the furious stuff when we think of modern movies, but when we think of the past we really only consider the classics. We haven't yet seen what modern movies will qualify as classic.
The 80/20 rule holds here: 80% of everything is crap. That applies to movies now, and it also applies to movies in the past.
There's also the very real thing of changing tastes. Movies are made to appeal to the taste of audiences in the time they're made. Modern tastes are different than the tastes of yesteryear.
I think it's not right to say that modern tastes are better or worse than older ones. They're just different -- but it makes sense that the ones aimed at different tastes will be a less popular.
On top of that, a lot of actually interesting content has the potential to cause shitstorms. Like, especially anything LGBT and women's rights won't fly in China, Russia, Arabia and lots of Asian countries. Black lead actors lead to massive shitstorms from the far-right in the USA and parts of Europe [1] - and so, producers leave all that "potentially troubling for sales" content out.
Everything "mainstream" is just the same bullshit now, white- and dumbwashed.
[1] Black Panther and the 3rd Star Wars trilogy were surrounded by some of the most vile harassment campaigns I've seen, for example
Or, movie studios have exaggerated the impact of (real, but not very numerous) internet trolls to protect their own egos from valid criticisms. The third Star Wars trilogy was an incoherent mess. And for reasons I still don't understand, the end of Black Panther was released in a rough half-rendered state. But the people making these films don't want to hear criticism of their baby, so online critics get dehumanized as "trolls". Rare instances of real trolling from the likes of 4chan get highlighted and blown out of proportion as a defense mechanism.
For BP, it was the same. The whine from the far-right about "who wants to see <N-word>s in movies", "we're being ethnically replaced", "this is our future" etc. was unacceptable.
I'm not denying, much less excusing that. What I am saying is that such trolls are an irrelevant minority who's voices are amplified by those to whom nutjobs are a convenient excuse for their own failures.
Black Panther sold many millions of tickets in America, and had maybe a few thousand 4chan-style trolls complaining about it. Am I really expected to believe those few thousand trolls were the reason the movie got less than flawless glowing reviews from critics, rather than flaws in the movie itself being to blame? And if the Star Wars trilogy failed to perform as Disney expected, it certainly wasn't the fault of trolls. Star Wars fans outnumber trolls a million to one. If the Star Wars trilogy under-performed, it was because the Star Wars trilogy was flawed. Trolls are just a convenient excuse for the people involved in the production who don't want to face the facts about the quality of their product.
The worst thing are the stalkers that don't leave it at comments on Twitter but cross into real world intimidation (e.g. invasive photos, ordering pizzas, ...) to outright violence - you never know when they are gonna hit.