People with long attention spans can still focus on things that take very little focus, like short-form videos. But people with short attention spans have a hard time focusing on things like books, or even movies. So having a long attention span opens up more intellectual avenues for you, without restricting any.

Yes, there's always some puritan attitudes involved in how we talk about this. But I do feel that people who can't read a book because of attention issues are missing out on something.