It’s no secret that the ELT industry has a discrimination problem. Apparently it’s really bad in Korea, especially if you are black. In Vietnam, you will be discriminated against if you are vietnamese (regardless of your qualifications). I sent this joker my CV and I talked to him on the phone so he clearly knows I have a CELTA and have a native accent.
There is a small movement within the industry to fix discrimination: see
http://blog.britishcouncil.org/2014/07/18/is-it-always-preferable-to-employ-native-english-speaking-teachers/ and http://teflequityadvocates.com/ , but their cries will probably fall on deaf ears. The people in power (e.g. Cambridge and British Council) need to walk the talk. Let’s see some more people of color in english textbooks and let’s see some accents aside from British and American in the recordings. Then maybe attitudes will start changing.