For users, yeah there's no reason to disable screenshots or any other functionality that a user might want to do on their own hardware that they bought and morally should be in control of.
But for app developers there are a lot of reasons they might want to do that. Disappearing messaging apps like Snapchat, ticket QR code displaying apps, stock footage apps, ebooks, and more.
It's just that Google has decided that that second group of people actually owns your phone, not you.
This analogue loophole really makes me realize that if you need to stop a screenshot/screen recording for security/whatever, you've got a design problem. And this is specifically applicable to services like Netflix.
But for app developers there are a lot of reasons they might want to do that. Disappearing messaging apps like Snapchat, ticket QR code displaying apps, stock footage apps, ebooks, and more.
It's just that Google has decided that that second group of people actually owns your phone, not you.