I wonder if this is a PR thing, to save face after flipping the non-profit. "Look it's more open now". Or if it's more of a recruiting pipeline thing, like Google allowing k8s and bazel to be open sourced so everyone in the industry has an idea of how they work.
I think it’s both of them, as well as an attempt to compete with other makers of open-weight models. OpenAI certainly isn’t happy about the success of Google, Facebook, Alibaba, DeepSeek…