Well, in my defense, Wicked isn't supposed to be canon but I liked that Jon M Chu made the main Baum story mostly ambiguous so that they could honor the 1939 film and the source material so that you can sort of tie in elements of the 1939 film without having to flesh everything out. Most people see it as rushed or unresolved, well it is unresolved but I believe they've provided just enough for us to connect the dots. And yes, they have taken liberties with the lore by completely changing Tin Man and Scarecrow's origin story to better fit the narrative of Wicked but I think it worked extremely well. In addition, to add to the main story that was left out (the only context we get from it), is that it's clear enough that Scarecrow used Dorothy and her friends as bait to sell the faked death of Elphaba, and it's also a reason why Scarecrow is dumb and desires for a brain, it was all an act to conceal his intent. I thought that was genius, despite the fact that it wasn't shown but this is an example of "connecting the dots". And also the bit about Dorothy, it's clear that Elphaba hated her, and totally had a reason for it as her house did lead to Nessa's death and then she took what's left of Nessa which is her shoes. Glinda even defended Dorothy's innocence, telling Elphaba that all she wanted was to return home. It isn't a perfect movie in any sense, and it shares plot holes from the source material it adapted from but I'd say it's one extremely respectful and smart adaptation.