The Catholic schools around here use iPads but they have a disciplinary system also and the ability to enforce it.
I was in a situation where they used computers for testing an incoming Freshman class. It was a teacher-intensive mess to supervise.
It’s all in implementation and policy. Block You Tube, Facebook, etc. It’s doable. I set up an entire school with tablets with managed content. Even the teachers couldn’t buy anything without approval. Kids and parents sign a notice of responsibility and the kid keeps the same device through their time at the school. Lock them up in a charging cart until ready to use in class and then you have the kids sign them out. Parents are financially responsible for damage. You set up the appropriate filters and policies and they are a fantastic tool to supplement instruction. Notice I said supplement, not replace. Sounds like this district was clueless.