There have been some incidents involving a Mac telling a user that the ChatGPT app is malware and moving it to the trash. Overall, ChatGPT isn’t malware, and there’s a very easy fix.

It’s too late to just update ChatGPT, you now have to re-download it from the developer

It’s too late to just update ChatGPT, you now have to re-download it from the developer
This is not Apple making a judgement on the value of the ChatGPT app on the Mac, it’s macOS doing its job. Since 2022, macOS has included Xprotect, a feature you never usually need to know about, but which safeguards the Mac against malware.
In this case, as reported by users worldwide on social media, Xprotect had concluded that the ChatGPT app contained malware. Therefore the whole app is suspect, therefore macOS moves it to the Trash and won’t launch it.