Signal lacks other compliance features. e.g. message archiving
It might be good if you're a journalist, but it's not as good if you have compliance requirements beyond confidentiality.
godelski
Wouldn't this be pretty easy to roll your own? You could set up different servers like Molly does. Or you could just recompile the app. Or you could force link it to a desktop session? Just spitballing here
kube-systemOP
There are already forks that add some of those features.
It might be good if you're a journalist, but it's not as good if you have compliance requirements beyond confidentiality.