Yes, “yellowface” is absolutely a thing. It’s not a controversial stance to believe that an actor’s ethnic background should match their characters. When it comes to other identities (religious, disability, LGBTQ), the discussion is more nuanced. Often, it’s an economic argument — extending opportunities to actors who might be traditionally excluded. Sometimes it’s about wanting an actor who plays an individual character rather than an identity’s stereotypes. Sometimes marginalized folks just want someone who represents them on set with the hopes that they won’t be disrespected. These concerns are valid, and “duh, that’s why they call it acting” is a fairly weak response.