I'm an IT professional and I think I know few things about how can modern technology and all those screens fuckup relationships. That is the main reason why I decided that I don't want my kids to be in front of the smartphones, computers and TV screens all the time. And that is why our home is almost free of those distractions.

My screen policy

The youngest two kids (10 and 12 years) tell me all the time that they are among "the only ones" in their class without a smartphone. The oldest daughter is 15 and I gave her a smartphone a few months ago when her grades were at the level we all agreed on. But, again, she said that she is the only one on the whole school who has a father that's willing to pay for an app that limits her screen time on that magic black box with applications.
And if you consider that we don't have a TV set in the living room (but we have a large projection screen on which the whole family watches movies from time to time), that we have only one family computer which sits in living room and that we don't have game consoles and other gadgets, then you can conclude that I'm quite conservative for this day and age even though servers and computers are my butter and bread so to speak.
Will my kids be deprived of some "healthy" contact with the new technologies? I don't know for sure, but I doubt it. I may even be raising up two hackers who need to get pushed into the right direction to end up on the whitehat side of the story. :)
How can I be so sure my kids won't have any major frustrations because I'm limiting their time on computers and phones?
Firstly, I'm really not so conservative father after all. They can play games and surf the internet under my wife's and mine supervision. And secondly, they have shown incredible prowess in social engineering and "hacking". Let me explain.
My passwords should be safe because I take a great care not to reveal them, to change them regularly and I think they are complex enough to be resilient to brute force attack. My wife's passwords, on the other hand, are quite a different story. And two sons know that.
As I now look back to what was happening in the past I can see it was a daily routine that after my wife changed her password, the kids would call us after school to work (using a landline) and complain about how they are bored and if we could unlock the computer remotely. But after few weeks those calls stopped.
Wife and I assumed that they just got tired to call us. But boy were we wrong and far from the truth. :)

Social engineering skills

I'm sure even Kevin Mitnick would be proud of my two boys. They used some pretty sophisticated social engineering methods to get my wife's passwords. Every time. For a year if not longer.
I'm sure everybody who was a victim of a pickpocket would know what I'm talking about. They teamed up and together they created some kind of overload on my wife's senses. They were all over her when she was using a computer. Distracting her, touching her.
That caused her not to be careful when entering her password. They used (boy I love this expression) shoulder surfing, peeking over her shoulder. And because my wife does not type blind, she looked at the keyboard not being careful enough what was happening around her.
One of the boys took the opportunity and took over the mouse and pressed that password reveal icon on the Windows 10 login screen so he could see the part or even the whole password as my wife was entering it. Together with earlier mentioned "buffer overflow" attack on her senses, they got the password(s) in no-time.
We soon understood that we were very naive and the kids know very well what they were doing. And because of like father, like son, we realized that we have two hackers at home.

I gave them a hacking problem to crack

I know that it would be stupid and counterproductive to punish them. After all, they showed some skills. I'm sure they don't need lecturing and punishment. They need some guidance to channel their creativity and to sharpen up their skills. And so, I gave them a real-life problem that they needed to finish by the end of the semester. The prize was a visit in one of the theme parks in Italy. Quite a motivation, I would guess.
I made a special local account on the same family computer and they got the task to break in through that account. They needed to get all the info by themselves. I was giving them only some hints every now and then.

Hackers doing research

They got really serious about hacking and they visited the public library where they would gather all the info they could get hold of, surfing the web, watching Youtube videos. Soon after they asked for few tips. By the questions they were asking I knew they were on the right track. Three weeks later they wanted an 8 GB USB flash drive. Ups, they were close. They really were.
And the day came: "Daddy, let us demonstrate you the hacking of the account". Ok, they were ready. And they demonstrated, without a flaw. Booting up the computer from a USB drive, choosing repair computer, opening a command prompt, typing the commands they got on the internet and effectively changing the password for the designated account.
And voila, they were in. Boys were happy because they knew they would get their theme park visit and I was happy because they learned some real-life sysadmin skill.
In technical terms what they did was not hacking, of course. Changing password on the local account of Windows 10 machine is a quite well-documented procedure which I use almost daily.

What I've learned

1. Kids are great social engineers.
2. Kids need some fine line walking.
3. They need right motivation and guidance.
4. Being naive is something I should embrace. Kids are always smarter.
5. I'm not doing them any harm by limiting their screen time.