To spell it out, you're asking people to get together and talk about breaking the law on a platform hosted and run by a company in the US. A platform that has been caught snooping private messages to find justification for banning users from the platform who have not broken any rules anywhere outside of those private messages. A platform that requires most users to register a real cell phone number with their account. A platform with mobile and desktop clients that are well documented as big ol data harvesting machines (seriously the wireshark logs are just stupid with the amount they're sending back to home base).
Not to mention that for everything Discord does, there are secure encrypted altrnatives. Some p2p, some selfhosted. Not all shoved under the same roof, but they usually are better quality anyway.