The guy has had a vision in his head, one that's compelled him enough to sit through the process of converting, scratch building and painting this diorama to an excellent finished detail.
His reasons for doing this are completely irrelevant. It is a work of creativity, it is art. It is provocative, it brings more than one topic of discussion to mind.
Nobody here has the right to say it shouldn't be. Ever tried telling an artist what he or she can or can't do? 90% of the time our response is an amused "Fuck you." And why should it be anything else? Censorship of any topic has no place in free creativity. As long as nobody gets hurt or exploited, there is no harm.
If it isn't your thing, you DON'T LOOK AT IT. You turn the other way you ignore its existence. That is all.
Nonsense is our Salvation