No one will ever agree to the notion that you can't play somebody completely unlike yourself, or that you have to cast the role from the group you are characterising.
Actors are picked based on who is the best one for the job which includes things like popularity, and the indefinable charisma - that element which which mesmerises audiences, but is difficult to analyse.
It would be a complete waste of time to pick someone who, for instance, was trans, but was not known, had no charisma, and couldn't rake in the money.
No one will do it.
I'm sure, if you can find someone who characterises the role, due to personal experience, but can also be successful, then of course.
Until the success of a film will rely entirely on the characters own personal experiences, then it won't happen.