Why don't open source alternatives just copy the UI to make it easier to switch? Everyone knows the GitHub UI and it's intuitive. I'm happy to get more privacy and freedom, you don't have to make a worse design just to be different. Fluxer figured this out and they're the best discord replacement imo. https://fluxer.app/
Good luck. The amount of features and screens on GitHub are vast aside from just those code / issues / PRs tabs.