I wonder how much leverage Signal has here, if any. I have a friend whose partner worked at a high level in the UK Gov in the foreign affairs area. Still don't

I wonder how much leverage Signal has here, if any. I have a friend whose partner worked at a high level in the UK Gov in the foreign affairs area. Still don't have any idea of what they did exactly, other than vague but incredibly interesting stories. They mentioned it was the app they were told to use for communication with official contacts. This was a number of years ago though.