Nobody likes reading the fine print, least of all when you’re just downloading some 3D model. While printing a copy for personal use this is rarely an issue, things can get a lot more complic…
That's not how copyright works. Copyright is a legal concept, not a technological or physical one. If the intent was to be inspired by a 3DBenchy and it's not "transformative" (as in, into a different medium from a 3D model entirely), it's infringing. It doesn't matter how many vertices in the mesh are different if the person making it started with a 3DBenchy in mind.
At best, if your intent is to mock the original, you try to argue that it's parody and thus fair use, but it would still very definitely be a derivative work regardless. Any further downstream modifications would thus also be assumed to be infringing the copyright of the original unless they were (successfully) claimed to be parody too.