I have only managed to get one friend on signal. I got my wife on Whatsapp before signal existed (and before Facebook owned Whatsapp) for traveling outside the country, and now she won't switch.
Americans overwhelmingly use SMS (RCS) for everything. And Facebook Messenger 🤮. I refuse to install that even though I'm sure Whatsapp isn't any better by now.
As far as I know, Egypt was just a story from the Bible. There is no archaeological evidence of a Jewish population of size in Egypt.