I've been attempting on and off the last few years to spin up a non federated matrix server in my homelab to make an alternative to discord for my friends. I run into some various issues every time. I'm pretty good at tech, but for whatever reason the barrier to getting a working self hosted matrix server seems too high for me.
I really would like to move to an e2e encrypted discord alternative. Maybe someday I'll be able to do that with matrix, when ether it gets easier, or I get smarter.
Have you seen this repository[0] that automated most of the configuration? I have a similar goal to you (get family off of Google Chat), and I was pulling my hair trying to manually set things up. Now the hard part of getting them to migrate...
[0]: https://github.com/spantaleev/matrix-docker-ansible-deploy