These robo-takedown outfits are a form of spam in my view. If you are publishing large sites or include user generated content you've probably run into them more than once. From what I've seen claimed as infringing it is obvious that there is no human review process. Compare to the expense of filing court actions for bulk frivolous claims.
Typically they can be ignored if your hosting provider is game. Their first step will be to try to harvest your data by provoking a response. If you do feel compelled to respond, be sure to run it by someone with legal expertise. Anything you say can be misconstrued in the worst possible way.
At the end of the day, these companies want to produce metrics to say, "We defended your brand from N number of verified infringement incidents this quarter. Based on the escalating threat volume, we recommend giving us more money going forward..."
IANAL, but I would avoid interacting with these 3rd party trolls. If they truly want to send a demand letter, ChatGPT's lawyers should send it by courier and obtain receipt of your signature. Until then I wouldn't take it seriously. This doesn't even rise to the level of a genuine legal threat or registered demand letter. It is more of a scare tactic.