I just opened my iphone 13 box and there is a paper slip that says "before use, please refer to the user guide <url>" Along with a few of the main safety points printed on the paper itself. When you start the iphone the first thing it makes you do is log in and then click through a series of tips and tricks pages but nothing stops you from clicking next through them without reading. They then put an app on the phone by default called "Tips" which explains all this stuff with images and videos.

At some point you just have to admit that there is realistically nothing more that can be done. Users don't want to read the manual because they can use their phone perfectly fine without it. They might not notice there is a nicer way to move the cursor but it doesn't really matter.

There is a manual and it comes preinstalled as an app out of only around 10 apps on the default screen and yet people still complain about the lack of a manual. I really don't know what they could do other than locking the phone until the user completes a quiz on the manual content.