I personally hope that nothing changes in this regard. I think it’s great if everyone can use the content that was voluntarily posted online for the whole world to see.
Speaking as someone with 100k rep on SO, I don't mind them using my answers to train the model. What I object to is when the resulting model is not then itself posted online for the whole world to see. If OpenAI actually shared the weights for GPT-4, I would consider it an ethical trade.