Uh He never said it has to be self-hosted though, so this already sounds like a strawman argument. Only one who has mentioned self hosting in this thread is you.
People want something that is secure and respects privacy, they could simply use the Matrix channel, or create their own Matrix space specific to lemmy.world , both of these would be better options for the users than to try and get them to use Discord which is a proprietary corporate service that is not only prone to security problems but also has some serious privacy concerns due to being corporate owned.