Now, I think imposing limits in the open world is a specific challenge. To your point, you’ll see kids at restaurants on iPads. Well, now your kid wants iPad. You don’t give it? They start a shitstorm.
Our daughter certainly did not have access to an iPad at that age. Maybe she could use her mom's iPad (I don't have one) once every few weeks for a brief period. The shitstorm only happens a few times, they get over it pretty quickly.
It got harder once she was 9 or 10, because most kids have access to a phone after school. Once she got a phone and a tablet, there have been very clear time restrictions. A lot of kids hang around on devices all afternoon, the rule here on weekdays is that she can have some screen time before dinner. (I remember that also being TV time for us when we were kids.)
She was allowed to play on the Nintendo Switch when she was 7 or 8, but only fun, non-addictive games (the typical Nintendo titles) and no multi-player.
Hard to impose a device limit on a kid if that kid watches you use your device constantly. I’m not some hero here - constantly reminding myself to be aware.
Yeah, that is hard. I think banning phones from shared moments like (the time around) breakfast, dinner, or when having a cup of tea together is an easy and impactful move. Those are moments when they are also not playing, so it's a good time to be together without distractions.
My kiddos don't have that access either. They do have their own iPads but not with unlimited access. Most common usage: flights, long drives. Otherwise, no weekday or weekend usage for the most part.
As for the shitstorm, yes, they get used to your rule and calm down. But that was my point: lots of folks overreact and create the vicious cycle. Your kid complains, you give the phone, they shut up. Repeat. Repeat again. Now your kid expects the phone. And now you believe they will only ever stay calm if you give them the phone.
Breaking the cycle requires you to stick to your statements, but also, in public, to not give a shit about embarrassment. When you worry if you're disturbing everyone else or you feel inadequate as a part that can't calm a kid, you might give in. You can't!
PS: multiplayer games in my statement -> multi-player with me. Not internet.