I'm one of those people, but for a discord alternative, I think it's a pretty fair trade off. My WhatsApp groups are mostly under 100 people while discord servers get much, much bigger. The only thing I feel like would be viable would be one shared encryption key for large rooms that just gets shared between the members via a resource-intensive diffie-helman-like message once and then after that everyone just uses the same key.

Is there a group of people who use WhatsApp who care about e2e encryption and hold it as the standard? Surely its common knowledge that you cannot trust the parent company of WhatsApp, or its encryption since being broken.