Remember how awhile back Facebook added a bunch of pre-selectable backgrounds for text posts, because they wanted to encourage people to still post written content rather than just images and videos? That's kind of like what Sora 2 is intended for - it lets people who'd rather write a prompt than film something, create content for TikTok. Yeah, there's a certain irony in it being flooded with AI slop right around when it's supposedly coming under new ownership.
I think the initially lax guardrails are because it'd be really difficult to prove that the content being produced is infringing (as 10 seconds isn't even long enough to generate the average length TV commercial), and the brief "wild west" approach certainly got the hype train rolling. I think most of the lawsuits with any likelihood of gaining traction are going to be the ones argued from the point of misuse of copyrighted materials to train the models, not the hilariously short clips of Pikachu fleeing from the police.
At any rate, they are tightening the guardrails, which probably is a good thing anyway, because that means people who actually understand the basic concepts of screenwriting will probably stick around to make their original content, while the "South Park but Rick and Morty show up and make derp faces" crowd get an error message and leave in a huff.