That is the same way I see this, you can learn through any source but just don't publish them the same way, but if you must, reference it, it is as simple as that. Chat GPT is not lesser than the books, information and articles we sort for and read both online and offline, they are just information, but the issue is that you should not plagiarise, you should be natural and creative in writing it down and I do not think there should be any other special rule/consideration for that.
If you'd followed this topic in different places on the forum, you'd new that AI makes lots of mistakes, it is inaccurate. So when you compare it with books, it is an incorrect comparison. And main problem is that AI text is written in formal style in good English and that increases the reader's level of trust to that text, because it looks like written by some person deeply knowledgeable about the topic. And when you have reliable and fake facts in a mess, how can you know yourself which are which?
AI chats are to have fun, not to learn from them. And that's why it is even more worse when someone posts AI texts without references: an unprepared one even don't have a chance to know that all that rubbish is written by AI.