I think, the more power available to a person when they are in distress, the less need there is to identify their distressors as part of a bloc or a movement. The amount of time spent determining how racist Taiwanese people are against certain classes of people should by inversely proportional to how much privilege that class of person has and how much influence the individual can bring to bear when addressing the racist event. In general, the more the person can use their privilege to ameliorate their distress, the less value there is in noting that they were distressed in the first place.
Plus, since the issue is taiwanese people suddenly worrying that they might be racist because a nice white boy's abuse video went viral, we're talking about a positive process. Their society, at least at the edges, is gaining some ability to be less insular. Being "racist" ie irredeemably so, is something different.
Apparently I using a claim that racism is intractable. A racist can't see beyond race. Identifying a racist would suggest that person isn't merely reacting poorly or in bad faith. Then again, intractable racism offers normal people the tool of bad faith, so shrugging off some rant as "merely" bad behaviour is questionable.
I don't know. Why do you want that guy to be the racist?