I know right anything but leaving discord.

This is a case where you don't actually need to "social!convince" anyone. It's piracy, you are aiming for people who already want to go where the links are. You put the pirate stuff over IRC, people will go to the IRC. You put it on a Discourse forum, people will go to the Discourse forum. You put a catgirl to weigh their souls beforehand to check they are human, they'll praise the catgirl.

This is why we need it to be socially unfashionable to use discord. I coined the term "Discord bro" to refer to people who love and use discord exclusively. I entourage using that language when talking about the problem online and not being understanding or compassionate towards people. Convenience is a big reason for people using it. Stigma is a reason to switch.

Some people can have a fatigue where they're tired of just moving platform to platform. Communicating platforms is heavily saturated to where, nobody would feel that grand of a difference going from Discord to that platform when they can still do the basics. People still wouldn't leave Facebook, even, despite that platform having largely corroded over the years.

Until Discord is like charging people to use it, people aren't going to budge. In a world where your privacy is circumvented whether you know it or not, a lot of people just shrug their shoulders at you when you present alternatives all like "ehh, cool" before just resuming what they're already using.