Modern motion pictures are made for people who temporarily or permanently lack the mental capacity to understand deeper plots. The other audience is too small to bother with.
Then contrast a 2000s movie to a modern film and if you want to feel really sad, contrast that to a high budget YouTubers content.
have been watched almost a hundred of hours of the early cinema (1920-1930) i found 2001 space odyssey boring as heck. had to go to a public theater to not sleep through, because the past 2 attempts at my house got me sleeping. cinema is a recent medium. it can go through a lot of stuff. and yet, you can find shallow films since the first era, till today. not every movie was made to be dense, slow or thoughtful. the 90s also had a bunch of shallow stuff
I believe it felt slow when it originally released as well.
Villeneuve commented on this a year or two ago in an interview where he pointed out that he hates the extent to which television has infected film with its focus on plot and dialogue at expense of what's visually on the screen.
I don’t think Inception is a great example of this. It has plot, but the plot is all texture. None of it makes that much sense, nor does it need to.