Corporations want a reproducible formula that can scale. Creating movies (and TV) is an inherently creative process. The people who end up running these businesses hate that but creativity doesn't scale. This is why reputation and track record is so important in getting any project greenlit. So the likes of Steven Spielberg, James Cameron or Christopher Nolan have a lot of freedom. They can't quite make what they want. A studio still has to bankroll the project and they may not like it. This is how Francis Ford Coppola ended up self-funding Megalopolis and, well, the studios were right to pass, let's be reeal.
This is also why we get so many sequeals, remarks and reboots. It's a property with a proven track record. That's so much easier to get greenlit.
The other thing that happens is that corporations (including studios) can only increase profits by cutting costs and raising prices. And this last one has basically killed the ecosystem upon which movies (and TV) depend. Let me explain.
Once upon a time, LA was relativvely cheap to live in. This allowed people to live there and work on getting their break while working flexible, often service jobs. Waittressing, hosting, that sort of thing. It could be anything, really. But it has to be flexible enough to take time off to go to auditions and jobs and whatnot. It is very difficult to make a full-time career out of working in this industry. If you're an actor and you, say, get a principal guest role on a TV series you might make $1000-2000/day but you only end up working 1-2 days on that every 3 months. You can't live on that. Recently there was a piece on the actor who played Sam in Lord of the Rings having to sell his house even though he made $250k for the 3 movies. That was over several years.
This isn't just for acting. Lighting, camera work, production, direction, editing, writing, special effects, costumes, etc etc etc.
What sustained people were residuals and the relatively low cost of living. Residuals for TV basically got killed by streaming. A lot of movie projects became unsustainable when the VHS/DVD/Blu-ray revenue pipeline dried up. Matt Damon spoke about this.
But the other thing streaming killed was the network TV pipeline. A bunch of screenplays would be written (and sold). I'm talking hundreds. A handful of those would be made into pilots. These days that's maybe 10-15 per year. Previously it was 50-100+. A certain number of those went to a half then full series order of 22+ episodes. Getting one job could sustain you for the year.
Streaming came along. The residuals went away. Those 22 episode seasons became 8-12 episode seasons every 2-3 years if you're lucky. There was no syndication money anymore. Working people in the industry relied upon residuals in dry spells to make a living. And suddenly you needed 2-3 jobs a year instead of 1 and that's really difficult to get and, even if you get it, to schedule so they don't conflict.
And then obviously ticket sales in movie theaters were in decline and fell off a cliff with the pandemic. Starting in the 2000s you had the shift to save costs to places like Atlanta, Vancouver and Toronto. Productions started chasing tax credits all over the world and would immediatley leave when they ended.
Let me elaborate on just one example: writing. To get into this field you generally would start as a production assistant ("PA"). This would generally be an unpaid position initially (an "internship"). At some point if you didn't screw up, you might start getting paid. Then you'd be the assistant to a writer. This would give you experience in a writers room. Hopefully whoever you worked for would give you feedback and teach you things. The next step would be to get a staff writer job. Back in the day you'd get paid for 22 episodes. You'd be on set for filming and you'd learn production. Most producers came from a writing background. Eventually, this career would lead you to being a showrunner. Think Shonda Rhimes or Vince Gilligan or Matthew Weiner. Weiner in particular learned his craft and earned street cred as a staff writer on The Sopranos and he tried to sell Mad Men to HBO.
Now what happens if you get hired to write 8 episodes instead of 22 so you'd getting one-third of the pay. Your job is over before shooting starts so none of these young writers are getting experience to become producers and ultimately showrunners.
It's a bit like how some companies stop hiring juniors and just overwork seniors with the threat of layoffs. Well, those seniors used to be juniors. Don't hire and train juniors and eventually there won't be any seniors. Same thing.
I guess the short version is: streaming killed Hollywood.