> It felt to me that Codex created a much simpler solution in terms of code architecture than Claude.

Wow, I made exactly the opposite experience. Codex loves to make things as complicated as possible, even ignoring instructions and predefined skills. Claude behaves way more pragmatic. Maybe depends on the type of work one does, or even which programming languages/frameworks are used?

I have the same experience. I have passed Codex's code over to Claude (Sonnet mostly) to simplify it and it did a so much better job. Codex couldn't comprehend a simpler solution no matter what.