In order to make it into a Discord or Zoom competitor you would need to solve far higher bandwidth things like HD video and low latency audio, and both of thouse are fundamentally very different things for a server to handle as compared to high latency short text messages.
That falls into the same two fallacies as the ones of complainers against Youtube alternatives:
that in order to offer an alternative to a service you have to replicate all of it
that you have to provide an alternative to only one service
Like, really, you don't need to replace all of Discord, only the parts that matter. The alternative to build not to Discord but to "Discord is being used for documentation" already exists, it's called web forums. Ditto, the alternative to "Discord is being used for communities" also exists, it's called XMPP or IRC or Matrix depending on who you ask. The alternative to "Discord tracks user data" is simply called "you don't do it", etc.
Like, we are literally on Lemmy. Just about the first thing that we Get It from the internet is that centralization is bad, be it Products or Services.