> Silent phone usage doesn't impact the class, it impacts the individual using the phone.

That’s just not true. You decided to attend class, you are taking up a seat. You count toward the outcome for the class and what you do and don’t do affects the class as a total. If you decide to half ass it, that affects the class. At the end of the year if every student fails. A teacher can’t just go: “but that’s not a problem with the class, that’s an individual problem for each student, the class was perfect they all individually just weren’t good enough”