I would agree if the post by Signal would say "Hey, we know the server code hasnt been updated in a while, yall have been asking, so here is the updated source and this is the reason why. We have working to incorporate MobileCoin yada yada"

People have been asking about the server code for a while, with zero response or even acknowledgement.

No explanation why, no apology.... just boom, new crypto support in our server. Trust us its cool.

They knew this would be a bad look from the get go , to they did it in secret.