Relevant story: In 2015-2016, I was the commander of a few hundred new troops going through their initial Army training; not basic training, but the subsequent stage where they had a bit more freedom. When they violated the rules, I had the power to take away those freedoms, fine them up to a few weeks of pay, etc. Most of them endured that without blinking an eye.

Eventually I confirmed with the lawyers that I could also take away their phones, and that broke some of them. I mean that I had troops break down in tears in my office when I informed them of the punishment, and some went to extreme lengths to circumvent the punishment and secretly gain access to another phone. (They still had laptops and Wi-Fi, by the way, along with permission to borrow a phone if they needed to make an important call.)

The Army has studied this a bit and found that not allowing troops to have their phones during basic training is a significant obstacle to recruiting right now.