It sounds like it has no CI / merge gating solution. This doesn't look like a substitute for pull requests -- just a way of sharing edit history.

I don't buy the argument that being able to trace down the initial LLM prompts that led to a line of code will meaningfully accelerate review. That's just like a more advanced git blame. Reviewers will need to understand the code for themselves. A more advanced git blame doesn't really help with that

Just looking at the final version of the PR without all the intermediate history may be better since it won't sidetrack you with half-baked thoughts and assumptions from the development process. You can just focus on the result

There are cool things about this, but I'm not convinced it's actually useful. Even less convinced it's a replacement for pull requests. GitHub isn't great but I don't think this is really tackling the problems with GitHub