Why not just trust people to keep their phone in their pocket when out at a social gathering that was formed for the expressed purpose of disconnecting? Wouldn't that also help the person break the habit of checking their phone frequently while also knowing it is still there?
A few years ago, I realized my screentime was getting out of control. Being a person who has a history of substance abuse (and recovery), I recognize addiction when I see it. So, I took some measure to minimize my use.
1. Remove all non-essential apps. Games, news apps, social media...basically anything that was not helping me get something done. I ended up left with email (work) any my banking or payment apps, while all the "fun" apps got installed on my tablet that stays at home.
2. Use a minimalist app launcher overlay. It's actually crazy how the removal of graphical icons helps, turning everything in lists of words, making you have to think about why you just unlocked your phone and find the specific app instead of something like "oh, there's Discord, I might as well check that while I have my phone open. These launchers also tend to have built-in blockers for notifications.
It seems like these were two simple things, but they were not. Especially at first. For about the first month, I found myself pulling my phone out for no reason, since the trigger that was making me do it (boredom, anxiety, FOMO) was still there, but I learned to cope with them and eventually they faded.
I would not have accomplished that by handing my phone off to other people, which actually makes me more paranoid about what's going given modern privacy concerns. In the US, we even campaign against handing your phone over to law enforcement since the implicit trust has been broken one too many times. Do Europeans share this anxiety?
There are places/"events" in Europe where people keep their phones off seemingly without problem (ex. going to the church). But they still have their phones so if there's an emergency, one can just go out the building and pick up that call.
The problem with events is lots of times, people don't go to them to knit together, they go there for networking, so then getting someone's LinkedIn/Instagram/Etsy/... is (unfortunately) the end goal. If we could change that, I think most people wouldn't even need to take their phones out. Perhaps an after-meetup list of all attendees with their LinkedIn/socials? But then again we're at the privacy concerns.
In all honesty, though, I'm the type of person who would actually show up to knit. Networking tends to be an annoyance, to me, but I also forgive it since I understand that it can be important and lead to some great opportunities. When I meet people, I usually don't ask about what they do for work. That will come out in the natural course of conversation if the person enjoys what they do. If not, then I'd rather talk about something else anyway. Typically, I like to start with people's hobbies and interests. In my experience, you get a deeper connection that way.
Perhaps doing away with the "networking" mindset is the key? We have to find a way to make the focus on the experience, as opposed to forced meetings/relationship, which work mixers tend to feel like.
Using a real example from my own life, I went to a basket weaving class once. It was fun, but not something I wanted to pursue as a regular hobby. However, while there, I met the spouse of a practicing blacksmith and found out there is a network of "folk craft" people in my state doing really interesting things in terms of keeping the old traditional methods alive but incorporating modern materials. That saw me attending some blacksmithing classes and forging a few of my own knives.
It was all about the experience I was having with the people around me, through which relationships and talk of our careers naturally developed, leaving me to want to continue to keep in touch them.
Ever meet people that believe, to their core, that they are the exception? There's always at least 1 in every crowd. Can't relax properly when you're anticipating a selfish prick will reveal themselves at any moment.
Do people not encrypt their phones?
Of course some state actors might be able to break it with enough time but that should be enough to protect from most petty criminals.
Though I get that you might be unwilling to part with your phone. I guess you could just keep it at home.