About the controversy (cis playing trans)
I honestly do not get what this controversy is all about.
Cis men and cis women (please forgive me if I am using the term incorrectly) transition to becoming their true gender because they do not feel like they are in the right body. Prior to the transition, the person is at a stage where they are still a cis and don't want to be a cis because it is not correct to who they are. Thus, pre-transition transgender people despite being emotionally (biologically to a degree?) inaccurate are cis gendered.
The controversy is about not having a trans person play the role of Ray. However, this film takes place pre-transition and we might even not see the full transition in the end because the story is centered around getting his father's signature and most likely that will be the defining moment and climax of the film. So, 'About Ray' is about everything that happens prior to the transition itself. Prior to the transition the incorrect gender is cis rather than trans. So, why would is it more accurate for a trans person to play what at that point (despite being emotionally incorrect) is a cis character?
I can completely understand the arguments of a cis playing a trans character after the transition. But this isn't 'Boy Meets Girl' (2014) about someone who has already transitioned. It's about everything that happens pre-transition when the person was cis and trying to transition into their correct gender.
For argument's sake, for those who have a problem with this let's say Elle Fanning in reality wants to transition into becoming a man. Are you saying Elle would be more accurate to playing the role of someone pre-transition after the transition rather than while they are at the same stage? If so, please explain why trans Elle is more accurate to play pre-trans than pre-trans Elle.
How is a cis playing someone who is a cis at that point pre-transition inaccurate? Again please forgive me if I am using that term inaccurately as I am using it to state the physical gender pre-transition.