Certain the decline has been widely (but not universally) noted noted in many film genres - SF, superhero, fantasy (Dr Who, Star
Wars, Star Trek being those I am most familiar with). I dread the occasionally threatened but hopefully never realised reboot/reimagining/sequel/prequel to my all time favourite, Babylon 5. And has anyone made a romantic comedy post pandemic?
Why was 2015 significant, do you think?
2015 was when a confluence of factors all hit at the same time. Smartphones being universally adopted was one (you could see its effects on global mental health, such as rates of anxiety and depression, begin to hit in 2008). This lead to a whole host of other things, where things like social media were programmed to harvest
peoples' time like massive Skinner boxes, and this bled into even storytelling and media. Take Star Wars like you mentioned; the film that came out in 2015, The Force Awakens, seemed to exist almost entirely as an "Internet attention mine", everything about it, from the lead up to the story and worldbuilding (or lack thereof) itself, was designed to create as much stir and buzz on social media and the internet as possible, by being intentionally vague with its subplots and backstories it created endless pointless discussions online that were never satisfactorally resolved (a strategy pioneered by the director of that film with a series called "LOST").
When I mentioned "Skinner Box", this refers to an experiment done where they found out they could program pigeons to press a button at certain times by dispensing
food, any many have likened this to how social media hacks peoples' brain reward systems through notifications and the like. This even bleeds into video games, with games after that point having controversies over "Loot Boxes", which also attempt to hack the reward system of peoples' brains.
In terms of this kind of thing, I would really reccommend the 20th century author and media theorist "Marshall McLuhan", who's got quite a few lectures on YouTube. His work is mostly geared towards the sociatal and psychological effects of
technology that was novel at the time (radio and TV especially), but so much of what he talks about and predicts is so close to the modern day internet and society that it actually feels scary. He died well before all of this stuff picked up, but honestly his takes are so good and so comprehensive that I believe they're actually somehow superior to the opinions of people who are still around today. If you dive deeply enough, you find that him and
Tolkien were actually coming from the same philosophical roots, that being THE WORKS OF Thomas Aquinas (I first realised this when I recognised the similarity between McLuhan's observation of technology as an "extenstion of humanity" to Tolkien's idea of
the One Ring being an extension of
Sauron), so I think he should be of extra interest to Tolkien fans.