And I am waiting for a way to use Signal without it ever touching a smartphone) Right now I have a Graphene phone so I can trust it (so Molly works), but before that my phone (like most phones) did not support any degoogled OS. While the laptop (like most laptops can) was running Linux easily. Yet, you have to either use an Android VM or a frustrating command-line client to register!
Yeah, true! However, you also have to trust their server not to log what is available to them (including your whole social graph), while with XMPP you can SSH into your server and see that its retention is exactly as you expected. But yeah, the issue remains when interacting with other servers - tho even then there the data is more evenly distributed between different servers with different owners.