To answer the question posed in the title: if you’re processing images given to you by strangers, you should normalize RGB values by 255.
The author isn’t advocating for you to do so. They are just exploring the two approaches. Even in the sentences following this one where they mention where 256 might work, they conclude with your colleagues breaking it all anyway by using 255.
255
Don’t break convention
The author isn’t advocating for you to do so. They are just exploring the two approaches. Even in the sentences following this one where they mention where 256 might work, they conclude with your colleagues breaking it all anyway by using 255.