I have not tried it yet but I was also thinking of a setting that you could choose to get notified when someone is around you that has (x) same topics as you.
Discussion
The notification is already present:

No I mean a new setting. Right now It notifies if any topics match. A setting to change that to say, must have 2 topics in common to notify. Or 3 or 4..
No, it notifies only if there are topics in common!
(unless there are bugs)
You are misunderstanding me... I'm not asking a question. I'm making a suggestion for a new setting.
Actually, I don't understand the suggestion :)
Can you explain it again, please?
Current functionality: Notifies you when someone is near that shares a similar or exact topic as you.
Feature: add setting to increase the threshold for being notified from 1 exact or partial match to 2 or more exact or partial matches.
Say I have my notification threshold at 2, now I'll only get a notification if someone has at least 2 topics in common with me.