> The social graph lock in problem is well documented and well understood.
> i don't actually think it is.

Nitpicking but I was saying that the general social graph lock in problem (also referred to as chicken/egg) is well documented.

> i don't actually think it is. i don't know _anyone_ who uses just a single messaging app (and thereby a single protocol-level social graph). i have some mental map in my head: "if i want to reach friend A, i do it on Signal. friend B: Discord. friend C: SMS/tel/PSTN. friend D: Matrix". i think this is a pretty common experience these days: i'd hazard that my mix of 4 apps is on the _small_ side.

Hi! Nice to meet you! I use only one messaging app for all of my friends! It's called texting. As far as I know, all of my friends do the same, with the only exception being a few Internet-only friends where we use Discord.

The "mental map" that you are describing is exactly what I want to avoid. I am thankful that I have not had to make one yet, and when people tell me to use over-the-top chat apps like Whatsapp, I can see that the map must be made.

Just because this is the norm, doesn't mean I'm going to do it, especially since we don't do it now. As much as the interoperability problem between RCS and iMessage is an incredibly annoying problem, I would take a single unified messaging experience over some crazy fragmented one with a zillion apps any day.

> 2) coordinating large group chats.
> for as long as my peers are reachable by more than one messaging app, the odds of bridging between them isn't radically different.

A little confused by this, because Beeper and other unifying clients cannot in fact make groups which have participants on multiple platforms at all.

You said you need 4 messaging apps right now to communicate with everyone you communicate with. How many of those users also have all 4 of those messaging apps? Obviously it's not all of them, or you'd just use one messaging app. The fact that you need four implies that for a given selection of contacts, there is a chance that it is impossible to create that group chat, because there is no shared platform they are all on. Then you factor in that in some scenarios you need your contacts to include additional contacts, and perhaps your 4 messaging apps needs to grow to make it happen. And of course if you already made the group and you need to just add one more person then you might have to scrap and remake the group somewhere else. But then that group that already has some messages in it still exists, and people will keep texting it! Now you've split your group chats!

On top of this, I want to note that the mental map you have built is also prone to becoming stale. If one of your friends is on Signal and Whatsapp but prefers Whatsapp, but then uninstalls Whatsapp and forgets to tell you, then you very well may send a message to that person and have it never arrive. Of course they might bail out of both Whatsapp and Signal, and just go back to SMS. Now none of your messages will land- you didn't even think they were interested in SMS.

Sure, if they are a close friend its likely they'll let you know. Most people have 1-5 close friends. But most people also have far more contacts in their contact book, and some of those people they might only message a few times a year. That's not a mental map that can be maintained, or if it can, I don't want to.