Problems like those are unavoidable even on today’s Signal, because the service depends on internet peering relationships, internet service providers, mobile network operators, cell service, etc. Oh, and Amazon.

You usually don’t notice them because when any of those components experiences problems too often, affected users tend to get annoyed and switch to a more reliable one. (Also because you don’t expect to receive messages from as many people or as often as you do on Lemmy, so short outages are less likely to affect you at all.)

That would still be true in a distributed Signal, except that users could switch away from Amazon as well. Meanwhile, everyone not using Amazon would still be chatting during such an outage.