It matters to me. Claude code is more extensible. They put a lot of efforts to hooks and plugins. Codex may get the job done today. But Claude will evolve faster.

Codex is opensource though and there are quite a few forks already.

None of that matters if the model is worse. I say this as someone who uses both Claude Code and Codex all day every day — I agree with others in this thread that CC has much better UX and evolves faster, but I still use Codex more often because it's simply the better coder. Everything else is a distant second to model quality.