This isn't really about university classes but elementary school and high school, and no one denied that phones can't be useful on occasion – just that the downsides outweigh the upsides.
And many highschoolers are just one summer vacation away from a university classroom. Imho a great many highschool seniors are better behaved and take classroom time much more seriously than the average first-year uni student. We should not ball all kids together, as would happen under any total ban on a particular tech.
