Doesn't seem they've ever found a take they are happy with and they can't settle on one.
A previous writer who was on the project a while back, Alex Litwak, didn't like the idea of transformation, big muscular dude, etc. He said heroes don't look like He-Man anymore, they look like Adrien Brody, blah blah blah.
Other scripts I've read seem to struggle with how to execute the transformation from Adam to He-Man, how it should look come across. One script I read has Adam getting the sword, and he gradually starts growing muscular and swollen over the course of the narrative. Another one, the Justin Marks one, has him get the sword at the end and I guess it just gives him an armor level-up but that's it. It's not really a transformation into He-Man.
Of course, the original movie just had him as He-Man from the beginning and no actual transformation at all.
Thing is, the older adult fans are still connected the original cartoons and toys. Prince Adam, transformation, He-Man are big deals to them.
Movie executives don't get that. So you have a smaller teenage actor who with a sword can transform into an adultish muscle bound uber-mensch. In a cartoon you can do that, but how do you execute that on film? Do you get two actors? Can you shoot around that with visual FX?
But if he's He-Man from the start, there's no I Have the Power, there's no transformation, and those are some of the more beloved aspects of the character.