It won't be very challenging to get folks to move to Signal
Then just leave for Telegram which is infinetly better (their native windows client is just incredible compared to the other atrocious electron based chat apps) or even better for Signal which is not as feature rich yet but open source.
While missing the Matrix, Wire, and IRC options?
Telegram doesn't do e2ee by default, no thanks.
So you can turn it on for your group then?
Signal has an excellent app these days and supports encrypted group chat. But Whatsapp doesnt require convincing people.
Which is something the EU effectively banned last week, in the Digital Markets Act.