“If the school has a no internet at home rule must they also have rules outlawing kids from homes where the parents talk during davening in shul or dress less than tznius outside?”
Of course not. It is important to specialize. One yeshiva will cater exclusively to those who have no internet at home. Another will cater to those whose parents never talk in shul while another will cater exclusively to those who excel in dressing in accordance with halacha. Of course it will be important to have competent poskim available to ask a shayla to when there is a parent who has wifi on their smartphone, but the wifi is disabled at home if that qualifies as “no internet at home”.