On November 16th, Meredith Whittaker, President of Signal, published a detailed breakdown of the popular encrypted messaging app’s running costs for the very first time. The unprecedented disclosure’s motivation was simple - the platform is rapidly running out of money, and in dire need of donations to stay afloat. Unmentioned by Whittaker, this budget shortfall results in large part due to the US intelligence community, which lavishly financed Signal’s creation and maintenance over several years, severing its support for the app.
All your XMPP contacts will be gone from their respective servers if they shut down too. Case in point: DuckDuckGo
Using the current server distribution of my contacts, I would never loose more than 13% of my contacts if a single server shuts down. Federated systems are much more resilient against providers shutting down as well as takeovers. Think Reddit vs Lemmy, Twitter vs Mastodon, Signal vs XMPP.