Because the mission is visibly abandoned. There's nothing "open" about OpenAI. We may not know how the mission was abandoned but we know Sam was CEO, hence responsible.
In terms of the LLM's, it was abandoned after GPT-2 when they realised the dangers of what was coming with GPT 3/3.5. Better to paywall access to and monitor it than open-source it and let it loose on the world.
ie. the original mission was never viable long-term.