I agree they didn't really stay consistent with the real movie - there were scenery things they should have researched and didn't. This generation probably won't notice.
I'm glad they didn't stay consistent with the Julie Garland movie because
that movie wasn't consistent with the book. I listened to see if this new movie mentioned where Glinda was from. It did. She was from the south, just like the original work by Frank Baum, and unlike the 1939 movie, which made Glinda the good witch from the north.
It's been a while since I've read any of the books. From what little I remember, I agree that they could have done better canonical research, but it should entirely be based on the original books, not the old movie or any other story about the Land of Oz that was not written by Baum.
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The movie had a few themes in it that I liked. Oz praying to God not to die because he hadn't accomplished anything yet. I actually had that same moment in my life when a tornado hit my apartment several years ago. I could so identify with him at the time.
And I felt sorry for Theodora, seeing what happened to her. She was deceived and became evil from that deception.
The movie may not have been spectacular, but it was good. Knowing that both evil witches would be around when Dorothy's story will later take place, it was obvious neither witch would be killed in this story. That took away from the movie for me. Not that I wanted them to die, but that the ending needed to be more powerful.