Is this answer minimizing a bit?
You can use the Firebase login tools without the person identification stuff pulled in. Note that for companies failing to do this in a privacy respecting way, a savvy user can usually get granular at the firewall and get the login to work without the audience reporting. Which means you could…
Similarly, in my book, segment.io isn’t just “telemetry” so much as it’s killer feature of cross app audience persona correlation, so less about what’s up with the app, more trying to learn more about the users without asking them. If you were instrumenting the app UX and not trying to see who is using you, there are other choices.
A number of ways to do accounts that can leverage a person’s own IdP or other approaches where you don’t have to have accounts, e.g. most any channel the team or group can access will do to get in sync on a session start.
Regardless, and even if GitHub and e.g GitHub Orgs are your way, all of them should be optional since not everyone is desperate to team their cli.
Last, and sorry to put it like this, if you’ve “discussed it quite a bit” as a team, I’m not sure but maybe that gives me less confidence in your respect for security, privacy, and users.
I’d imagine that deliberate discussion backed by respect for your users and team know-how should have resulted in a different set of choices.