A messaging app is not like a personal app that you use on your own. Its value is not only in the software itself but also in the number of users. It took Telegram years to get 500 million users. Now people are being told, "switch to this other app, it's better", "look how many alternatives". How long would it take Signal to be an alternative to Telegram user-wise? And once they get there, some problem will pop up and then what? Do we migrate to a new app and wait 10 years to have almost all our friends there?