I don't think the business events is realistic. It would have to be huge, generic, and have a huge amount of people be very specific with their wants-and-needs, on top of the technical issues I brought up earlier.
Speed dating is called speed dating for a reason, you're supposed to be forced to meet everyone. Probably takes more time to setup yet another dating profile than it takes to simply go through the process.
From what I read on 222, their entire purpose is to get away from algorithms, apps, and whatnot.
Timeleft has, according to their landing page, six people per activity.
I don't mean to discourage, by the way. It's neat tech, I personally just don't see where it could best be used.
EDIT: I could see speed dating have some sort of "prompt" build on top of this. Say the app is rebranded to "SpeedDater" and the organizers said to download it. Then while in the event itself, the apps could give prompts or fun stuff to talk about in realtime, and then later you could eg. say yes/no after the fact, at which point the matches are unlocked. Not sure this requires the local-thing though.
222 and timeleft you start in groups of 5 or 6, but then there is the "after party" with all those small groups combined. That's where this idea first came from. I was at one of those after parties and I was like wait and sec, it's 2025 why does this feel exactly like how we did this in 1980s?
1. potential customers / vendors (business network event)
2. potential mates (speed dating)
3. potential friends (222.place or timeleft)
I'd keep my phone out at a 222 event if the app guided me into a group of people that all share a specific interest.