It’s on the person using any AI tools to verify that they aren’t infringing on anything if they try to market/sell something generated by these tools.
That goes for using ChatGPT just as much as it goes for Midjourney/Dall-E 3, tools that create music, etc.
And you’re absolutely right, this is going to be a problem more and more for anyone using AI Tools and I’m curious to see how that will factor in to future lawsuits.
I could see some new factor for fair use being raised in court, or else taking this into account under one of the pre-existing factors.