Perhaps some companies are trying to get ahead of the game. It they can demonstrate they are ahead of things it might be a bargaining point.
The google one was kind of weird because I wouldn't consider the app in question an adult only app, the account had aged to 18 from probably 5 or so years ago. And it is my first time seeing the option to verify age with a picture or government id like they have in the UK now.
Disney wasn't an age verification in the sense of the Australia/UK laws and I am fairly sure it was a demographics update to gather more marketing information for the option of a future advertising rollout. Just general enshitification.