- Streaming video can be done with Jitsi Meet
- Voice chat via mumble.
- sharing files can be done via pastebin site (if text form) or through other third party (like imgbb).
- custom emotes can probably be done by extending the IRC protocol to allow for embedding tiny images. IRC allows for users to send commands so I don't see why this couldn't be done.
- IRC can support this in a network.
- An IRC network can run on a computer the size of a shoe.
Discord meanwhile:
- Is only compatible with itself so if your system doesnt support the client or the web interface well you're boned.
- Has very little content moderation.
- heavy advertisements via promotions and NitroTM (their subscription service to access basic features like recoloring the interface).
- terrible UI.
- spyware and data harvesting
- no support for encrypted messaging.
- Network effect so groups and orgs feel compelled to choose discord just because its popular and relatively frictionless.
- shadowy corporation that the public doesnt really know the inner workings of.