How can one claim clean room if developed by a model? “Don’t use stolen code, yo”?

I'm not the Paint.NET developer (just a happy user of that software), but to me the moral logic would go something like this:

If Anthropic can absorb proprietary or GPL code into their models, which they rent usage of for tens of billions of dollars in revenue, and successfully claim that this violates no licenses, then I can also consider the output of those models "clean" for purposes of my software I give away for free.