Someone nabbed a lady's expensive phone on a public transit, and was immediately detained. That's some pretty heartwarming news. Not sure what you're on about, there have been a few articles lately about Taiwanese locals killing their relatives, stabbing each other during road rage incidents, and all the way down to small cases like a local saying, "hold on I'm going to grab some money from my car" and driving off instead of paying for her food.
Now I'm not disagreeing there's an anti-foreigner stigma out there. The one you listed about falsely changing an article that was about a Taiwanese teacher fiddling his students into a white teacher is a recent example. What I've mostly noticed is it's usually coming from people upset that white foreigners are making a (barely) livable wage from English teaching jobs with minimal qualifications.
I'm a member of 12 different Facebook groups pertaining to English teaching in Taiwan and I see BS like that every week. Just a couple days ago some local woman said something along the lines of, "It's easy for white foreigners to get a job here. You get hired just for being white. Even if you're uneducated and dumb it's fine, you don't even need a high school degree." That is the rhetoric you're referring to, complete fake bogus BS against white teachers in Taiwan.
And since I'm on a rant, and since you brought it up, I'm really angry about this subject and have a few things to say.
1. Myth: It's easy to find a job here if you're white.
Truth: Last I checked, if you're a foreign teacher it's required by law to be from an English speaking country. Many employers prefer an English teacher without an unusual accent, and foreigners are harder to come by than locals. Hence why it's easier for them to find an English teaching job, but it's much harder for a "foreigner" to find any other kind of job.
2. Myth: Foreigners get paid too much.
Truth: Most teachers in Taiwan make about $24,000 USD/ yr. The average yearly wage for degree holders in America is $72,824. I personally have bills from America to keep paying off, and a wife to support. This myth really pisses me off, that's why I called it "barely livable." Furthermore, I know many locals that make more than this amount.
3. Myth: You can get a job here just for being white, without any education.
Truth: Foreigners still have to follow the law, and that's illegal. Unless you're married to a local and holding a dependant ARC, you'll need at least a bachelor's degree. Many dependant ARC holders without a college degree struggle to find work, even with prior work experience.
Until this ridiculous stigma is addressed, you'll continue hearing the same rhetoric. But what you (and I) mentioned have nothing to do with this topic. You're comparing innocent teachers that just want to help others learn English to an actual thief, which may even be grand theft (if this occurred in America) since most phones these days are valued over $300.
Want to change it? Host something like a "march for teachers," showing positive support for English educators. Complaining about blatant racism online isn't going to solve anything.