I did, a decade ago, all my must have contacts have long ago added Signal or switched. Those that cant be botherd mehhhh i cant be bothered with them either.
Sadly in my country no one uses signal, everyone used either WhatsApp or Telegram or Facebook messenger for everyday.
I would love to migrate if everyone in my country use signal or other FOSS messenger app, because I'm sick to see WhatsApp become more and more patronizing every single update.
Unfortunately Signal has less features, is less convenient, not as pretty and generally unliked by people who don't care that much about privacy, which means it will never gather the critical mass to be able to move completely to it. All my contacts use WhatsApp, it's basically impossible to escape.
Can't set different nicknames between servers, and it's much worse at actually maintaining large group conversations. Compare how communities are managed in discord or telegram vs signal.