- There really isn't anything like a united "popular culture" anymore except in the very ephemeral sense of the latest memes on social networks. The cycle here is faster than anything before. Strong meme fads can coalesce and dissipate within weeks or days.
- Media production of all types continues to become cheaper, as far as the actual process of production. Visual effects, photography, and editing are all easier with modern tech and I would say cheaper as well.
- Economic factors: The disposable income of average people continues to become less over time, and property rents where theaters and such exist continue to increase over time.
it's not surprising that new movies and other corporate entertainment have to follow a quicker cycle, including making things easier to consume. Entertainment media is more disposable than it has ever been at any point.
It will be interesting to see if social media bans for minors will have an impact on this and maybe slow it down a bit, but I don't think it'll alter the underlying economic factors mentioned above, so it'll be interesting.
I don't know if theaters still receive hard drives of the movies they are playing, but it seems like something that could probably be replaced by a local storage solution and an Internet connection by now, so maybe in the next 10 years we'll see theaters show movies produced and released on quicker but lower-quality schedules. Something like TV shows - a new one each week for a low price. But at that point why even leave your house?