Concur and I have no issue with the crossover itself in stories. Fantasy is largely predicated on magic systems and creatures. Science fiction begins with known science. Maybe I should have been more specific and said “hard science fiction.” Some of my favorite stories contain elements of both, but sometimes I want hard science like Rendezvous with Rama, Red Mars, or Tau Zero. It can be frustrating to look through aisles or catalogs for hard science fiction and find mostly stories of magic. It’s a mood

But then again, as Clarke said, “Any sufficiently advanced technology is indistinguishable from magic.”