What is it?
I've converted from cmux to t3code and don't regret anything - would 100% recommend. The way I see it, apps like the official Codex need to show off new features immediately and before people create good patterns. (and old features stay frozen without a good reason) T3code on the other hand seems to concentrate on what's actually useful for people and making it super polished.
There are other git projects hosted on multiple platforms. Pretty sure linux kernel is hosted in more places than github, and kept in sync because it's based on git.
What research did you base this on?