I mean that students can access that capability through a plethora of district provided resources. In the US, nearly every classroom has a fleet of laptops. Students don't need to use a device that lets them screw around and goof off anymore than that lol
I agree that there is some benefit for classrooms without that technology, but, honestly, it's more detrimental to the students' mental health and learning process, regardless.
Most kids in middle and many in high school cannot psychologically handle/manage using their cell phone appropriately in class. We can't expect them to. They're kids. They take pictures of each other without permission (usually, generally, innocent, but sometimes not), they spend hours of instructional time scrolling inane crap on Instagram or Twitter or whatever, or they straight up play fortnite all class.
Most of these kids have not yet been equipped with the media and tech literacy skills they need to make good choices regarding their technology. This comes down to the inherent lag time in the field of education and while we began addressing this over the last few years, a lot of kids have been raised by smartphones more than they have been by their parents.
Until that connection between student and smart phone is treated with greater respect and understanding, which will take a massive culture shift, kids don't need to access phones in class.