There are some threads in the past where people have discussed origins of MOTU and He-Man. Some are from story-point and others are from creator-views.

I'd like to try and get some clarity on the issue, since there is a lot of information that has been surfaced in past years.

Personally I'm also sick of different sources always claiming the origin in all too simple sentences, that don't hold water.

I'm just spitballing here.
And if anyone would like to add any information or theories of how things evolved for He-Man and MOTU, it would be greatly appreciated.

Roger Sweet
Suggests 3 different versions of He-Men. Also I recall in MOTU-Chronicles interview, he mentioned that he had also written something about a She-Woman. But his idea was like a family around He-Man. Can someone correct me on this?
Very broad strokes about a action figure idea of a muscle man

Mark Taylor & Ted Mayer
Have had fantasy on their minds and they helped make the visual look for the characters, adding their influences in there.
Visual style from Vikor to the He-Man we recognize?

Donald F. Glut
Receives some action figures from Mattel and is asked to create stories and world for them. First four minicomics tell a story of their own about a barbarian warrior leaving his tribe.
Is the first one to write down a story with barbaric land of Eternia, where He-Man, Man-At-Arms, Skeletor and other first wave characters exist.

Mini-Comics done by DC Comics for Mattel?
Wave 2 of Mini-comics, continue with stories about these few characters that have been made into toys, giving larger concepts for storylines that can be expanded, like Goddess/Teela and Man-E-Faces.
Expanding from the First mini-comics the story for He-Man and characters in Eternia?

Lou Scheimer and Filmation Studios
Filmation Studios focuses on few individual main characters and through their stories create their own world, not like the one seen in mini-comics.
Gave Orko to the mix, bringing He-Man to a more light-hearted fantasy/scifi setting. Is widely recognizes as what "He-Man" is to children of 80s.