I never quite understood the stargate mythos. Did all the goulds live here on earth, which is why earth culture is so diverse? Ra and Apophis in Egypt, lord Yu in China, the asgard in scandinavia etc. That doesn't make sense because the system lords all control their own space right? It's hard to imagine one big happy gould family on one planet. But then how and why did earth culture come to adopt all the other gould cultures? I just don't get it. I actually really like the part about humans ultimately becoming one of the galactic superpowers at the end of SG-1 and Atlantis.

Obviously the worldbuilding and writing wasn't done under a microscope like tolkein level continuity and isn't meant to be taken seriously. It's a miracle SG-1 lasted ten seasons and they were all fantastic, even 9 and 10. Its success is mostly just good old fashioned terrific entertaining writing and chemistry between the cast and crew.