Depends on the jurisdiction—e.g. Germany[1] is known to be particularly problematic. But in this particular case, the model has been released under CC0[2], which has a fallback permissive license alongside its public domain dedication, specifically to avoid this problem. That’s why the CC0 is a thousand words long instead of a couple of sentences. Most sites hosting “public domain” works also use the CC0 or something similar.
NAL either but D. J. Bernstein [https://cr.yp.to/publicdomain.html] says that you can use a work under public domain in Germany same as any other country (e.g. copying), but there's a separate right to be credited for the work where applicable and protection for the author's reputation.
So if I made Benchy longer and turned it into a rendition of the Titanic, I can't claim that it's 100% mine and no one else had a hand in making it under those rules.
So if I made Benchy longer and turned it into a rendition of the Titanic, I can't claim that it's 100% mine and no one else had a hand in making it under those rules.