The Signal Server repository hasn’t been updated since April 2020. There are a bunch of links about this here but I found this thread the most interesting.
To me, this is unforgivable behaviour. Signal always positioned themselves as “open source”, and the Server itself is under the best license for server software (AGPLv3 – which raises questions about the legality of this situation).
Signal’s whole approach to open source has constantly been underwhelming to say the least. Their budget-Apple attitude (secrecy, i.e. “we can never engage the community directly”, “we will never merge/accept PRs”, etc) has lead to its logical conclusion here, I guess. I have been somewhat of a “Signal apologist” thus far (I almost always defend them & I think a lot of criticism they get it very unfair) but yeah I’m over Signal now.
A few years ago (2017?) I decided I would move messenger apps. The aim (and what I’ve achieved) was all my messaging going through a secure, private app.
In 2017, Signal really was the only option. Element (Riot, back then) was really bad and didn’t feature e2ee (which only got enabled by default last year!). XMPP was and remains difficult to use (not even many people here use it, how could I expect “normal people” to use it?)
I made the choice to use Signal, and I don’t regret it. I only regret that it has taken until now that we are starting to see a glimmer of a real competitor, in the form of Matrix. But a really competitor to Whatsapp and the like, back in 2017, just didn’t exist outside of Signal.