This is incorrect.
If I have ownership, then I can ask for money to allow you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce — that is part of ownership.
With Midjourney, for example, I own the images I produce (that is the terms of the agreement I made with Midjourney). As such, I can absolutely charge money for those images. Whether anyone chooses to buy them is an issue for the market.
All the AI programs have different licenses, some which go so far as saying you will help pay for their defense (that is the OpenAI/Dall-e license — it is a pretty ugly license).
But if I own an image, I can indeed charge money.