Because you're the 10th person commenting something like this every. single. time someone's character (whose race is NOT important to the character itself) is cast this way.

Yet all of you always 'innocently' start with, "not that it bothers me or anything...'.

Yes. It clearly does, otherwise why bring it up? When minorities and POC are told to 'stick' to our 'own' characters, those characters are either never brought to live-action/ production anyways, or they're voiced by a white person which defeats the purpose of telling us to find 'our own'.

Bane in The Dark Knight Rises? Makes sense to cast a white British dude with an Irish accent to play the Panamanian. Or John Voight in Anaconda.

Natalie Woods played the Puerto Rican lead in West Side Story, yet the actual latina was demoted up being the sidekick. Scarlet Johansson in Ghost In The Shell? Emma Stone playing an Asian lead? So whose role CAN minorities play?

This is where the frustration comes from - decades of having scraps thrown at animators, writers, and voice actors, then when they see a series or character is famous, they'll cash in with celebrities instead of established voice actors. Peter Dinklage was an embarrassing decision by Bungie - ended up having to replace him with a voice actor who is already doing this for a living.