There’s probably many of us who would say: Worldwide? Yes. Global? No. Indeed, it is doubtful that anybody thought in terms of a globe/sphere at that time. “The heavens and the land/ERETZ” was a cosmology of its own at that time. For most if not all at that time, their world extended to the horizon. That’s it. If the story dates from a later era, then they knew that there were additional lands beyond the horizon.
Perhaps there were other non-Adamic hominids outside of the Noahic Flood ERETZ. Perhaps their intermarriage with Adamic people after the flood spread the Imago Dei to all Homo sapiens after sufficient generations and perhaps that also explains why there is no genetic bottleneck left from the flood.
Of course, Genesis doesn’t state the name of the ERETZ (land) that flooded. We don’t know where Noah was when the flood started, nor where he was when he left the ark. (Nobody knows where the “mountains of Ararat”/“hill country of Ararat” was located. The ancients had close to a half dozen tradition-based location. Grad school was a long time ago but I think I recall Egypt, Arabian peninsula, India, and, of course, the Fertile Crescent.)
Obviously, because the Genesis account and the Gilgamesh Epic are texts of the ancient Near East, we do associate the flood with the Middle East. But the story could have traveled with the cultures, from wherever they originated, to their eventual home in the Near East.
I don’t claim any final answers. I just try to separate tradition from what the text does and does not state.