Having been a teenager once myself, I can attest that there's nothing in this world that'd more successfully ostricize a kid socially, than grouping them with other isolated kids.

I think it depends how big the group is. If the group is 3 or 4 kids, then yes, that will be a problem. If the group is larger where they can choose who their friends are and not be constantly surrounded by others with phones, then it might work.

Parents can't just get together and decide that their 14 year olds are going to be friends.

They've done that to decide that their babies are going to become a married couple for centuries! I jest, I jest....

14 is way too late to start, so you are correct.

My parents had the same idea but instead of smart phone use, it was religion. It wasn't so successful for them.

You'll need to move to a very few, probably-expensive places, or scout private schools. Probably not the cheap kind.

:-(