It's no secret that chink is a racial slur so deciding to use the phrase, no matter how well established as not being racially charged it is, can be a slippery slope.
I'm sorry but the phrase has existed 600 years, is in regular use, and meaning hasn't changed in he way other words have like gay or faggot. It's not a damn slippery slope. If people want to be that ignorant it's up to them but we shouldn't cut usage of well known terms just cause a small vocal minority can't wrap their heads around an extremely common usage of a word.
Chink as a racist term has probably been 100 years or so since mass chinese immigration in the west.