Well, of course not, because since some diffusion generation are deterministic, that would mean that a specific set of parameters is now copyrighted, so nobody else gets to type in that particular set of numbers into the UI without paying the copyright holder, which of course makes no sense.
Same reason you can’t copyright, say, cooking recipe for a burger.
Food and flavors aren’t copyrightable or patentable because of an explicit exclusion of them. It has nothing to do with “determinism”.
No. Recipes are not copyrightable because they’re largely functional things for instructing a process to create a food, which simply is not in the purview of copyright. Specific recipes could very well be patented, depending on the specifics. There are no “explicit exclusions” here.