it's very well thought out ! The features make sense.
UNFORTUNATELY it's not P2P ! all the messages pass by their servers :'( with Briar it's P2P....
weirdly they claim their way is better than P2P ! any comment on that ?
In my point of view, if messages are stored somewhere it's mean the can be process[^1] !
The EFF article is really interesting for everyone. ( I was aware of this )
Indeed no one should assume that his packets are not intercepted along the road.
But conceive an software that on top of that, specifically route the traffic trough his server not make it better (on the opposite in my opinion)
Even if the owner of those server do not process the data... ( This is relying on blind trust) those servers might be breached. (in addition to the systemic data recording, like in the EFF article )
Let put it simple, is SimpleX offer on the actual Internet (can't wait the next gen, GNUnet or anything similar) a similar level of Trust & privacy than Briar ?
The big downside of SimpleX is that it's not P2P and IP correlation by watching your traffic is possible.
SimpleX recommend to use Tor on top of it with for example Orbot. That's a good idea, but not the best to convince none-tech folks to adopt it. (it's already so hard to change peoples habit... ) Tor should be embedded.
As soon Tor is embedded I will migrate to it. SimpleX have nice thought features and it's easy to use.
Direct peer-to-peer connections giveaway your IP address to the person you're communicating with. Meaning anybody observing the network can see two people are specifically communicating with each other. Briar attempts to get around this by using Tor to obscure it.
But briar is using Tor as a relay, just like simple x does. The architectures are very similar from that lens.
To your threat model, ideally data does not rest on the network, but you have to assume any data that hits the network is being recorded by a bad actor to be analyzed later.