Is there such a thing as a non-creative person? I.e a person who actually thinks/knows/conscientiously decides they are not creative?
They decidedly don't want to be creative, they just want the clone of the thing. Actually, it's often how you get the work done. Too much creativity is a problem. Linus started his work on Linux kernel because he wanted a Minix clone. It was as creative-less act as it gets.
Take somebody who wrote OpenTTD, open Transport Tycoon clone. It was an exact replica of the original game (later of course people got more creative with it).
The same time could have been spent creating, for instance, Stardew Valley. The author didn't decide to make just a Harvest Moon clone.
That is roughly a difference between a non-creative project and a creative project.
Even if judging by surface appearance something is a clone, there might still be a lot of creativity involved "under the hood" i.e. in the implementation. In the case of Linux it was originally optimized for 80386 and is a monolithic kernel while Minix is a microkernel design. Fine-tuning it to run fast on 80386 must surely have involved a lot of creativity?
The open source clones you mention are arguably not technically innovative (or some other word that stems from “novel”), but I’d argue that releasing a clone under a permissive license is novel (and creative), too.
You can argue that on some level, yes, any translation is creative. But I don't think it's the same as writing an original novel (even if the result is bad). On some level, it's decidedly non-creative (and that's what the GP asked about), because you already have the characters, the story, the words. And apparently, some people are fine with already having all that. (It's even not deemed creative enough to be considered different for the copyright.)
Is coloring a coloring-book creative? Compared to making your own drawings?
As for that question though, I'll push it a bit further - is drawing an outline of a bird creative? I'd argue it's more interesting than the next person coloring the bird. But it's also decidedly less interesting that what evolution has done in generating a bird from billions of years of evolution.
But I'd say yeah, something was created because the artist had a desire for the bird, and then produced it. Or, the artist (for some definition) had a desire for a green bird, then colored it. Of course, neither the drawing of the bird nor the coloring was novel.
So as it's not an autonomous manufacturing process, it's creative. Your bones generating blood cells is not creative work.
Software that adds colors between lines isn't itself creative, but the person who developed the software used creativity.
* I'm not a philosopher.