The actor's ethnicity is practically a non-issue. Let's review the bidding:
Take, for example, the role of Susan in our hypothetical casting. She's described in a way that seems Latino, and her name is Hispanic (or Spanish). But what in that says she can only look one way? I personally know a lot of people who would qualify by both aspects, yet are in no way Latino by heritage. Should they be discriminated against because they aren't actually Latino?
From the other direction, heritage alone is utterly a non-qualifier in casting. My best bud's wife is Latina. But she has blonde hair and blue eyes. For any role requiring a generalized Latina look, she'd be a non-starter.
My point is simple: start casting people with their personal ethnic background as a requirement and you've moved into the realm of ethnic discrimination. Pure prejudice based on the past, not on ability to play the role. Now, I do believe that a scren adaptation of a book should at least try to capture the appearance of the character as described. Be that as it may, that's simply the ability to fit the role. Period.
Let's stop trying to separate actors (who are, last time I checked, still people) by their background and start trying to judge them solely on their ability to play the role as written.
I think we are on the same page, but you are missing my point.
I am not saying that a non-latina should be barred from being Susan.
I just think that they are enough really talented latina actresses that can capture the character, that it wouldn't be a problem to cast it authentically.
Personally my original choice for Susan was Kate Beckinsale.
Besides that the Susan on the TV show was a blonde white woman.
And yeah I know what you mean about blonde hair blue eyed latinas, I know one too.
So I think we agree, but I still think authenticity of ethnicity should be at least a factor when deciding.
for example a checklist when auditioning for a role.
1) does she capture the characters personality and attitude: check
2) does she look the part: check
3) does the actor accurately capture the characters cultural background: check
Not necessarily a requirement but a nice 2 out of 3 guide or something.
Being familiar with the culture can be crucial in some roles, maybe not so much here, but imagine an actor with no personal knowledge of a particular culture trying to portray a character of said culture, it could be very unconvincing.
Like whoever plays Murphy should be familiar with Catholic-Irish attitudes and traditions.
With Susan I don't think it matters so much, but with Shiro, Rashid, and LTW i think it's going to be a dissapointment to most fans if Shiro isn't some kind of Asian, and Rashid isn't some kind of Middle Eastern, and LTW doesn't look some kind of Native American.
But it doesn't mean that a talented actor couldn't pull it off even if they don't look the part exactly.