Racism bad.
With that controversial statement out of the way, the double standards of the people upset are astounding. In chapter 124 the bully called Koreans monkeys, and this chapter alluded to them being "yellow" rats...but getting called a bad name in return for that behavior is the end of the world.
They didn't react to chapter 124, so it's not that they are principled on the issue of not liking racist language (disclaimer, racism bad is the point of the story arc)...in fact the outcry mirrors the events in chapter 125 where it is explicitly noted that the bully uses his skin color to pose as the victim when he is many times the aggressor.
True Education has had severe violence, child abuse, torture, attempted murder, drug abuse, gambling addiction, sexual slavery, suicide, bullying, a religious cult, kidnapping, and actual murder (albeit in the backstory) amongst plenty of other bad things where a social issue is presented and then addressed. Think about that for a moment.
Bullies and vile people capable of some degree of redemption have been shown better paths and become better people through the actions of the protagonists, as brutal as they may handle things at times, and the point of the many arcs has been not just to see the guilty punished, but to see those capable of reform embarking on those paths. Even a man who abused and neglected his son was allowed to become a better person for the sake of his son, and so despite showing the awful way Humans can act towards one another it tries showing glimpses of sunshine through the clouds.
The social issue this time was racial tension and conflict in a school setting, an important real-life topic these days, and following the story beats of previous arcs chances are we would learn more about the circumstances of the school, the students, the teachers, and ultimately after resolving the conflicts reach an end point where the students involved are not mistreating one another based on immutable characteristics.
Had the perpetually offended crowd not screeched over a racist character (racists of all stripes exist in real life, I know this is hard to believe, Twitter crowd) being called a racial slur in return for their racism they would have seen a narrative arc where the situation gets diffused and the characters involved learn to not call eachother monkeys and such. Instead now a series that has had far darker content in it is being put on hiatus because their fragile sensibilities cannot handle a fictional character being called a bad word. In their crusade to destroy racism they are cutting down a story that was about to show how wrong it is to treat someone poorly over the color of their skin.
It'd be one thing if this outrage began at chapter 124, but it didn't: those who seek offense found it in the form of their chosen protected group while ignoring the exact same actions towards Asians a chapter prior. Did True Education handle it perfectly? Probably not, but it also doesn't deserve to get sidelined because a small but vocal group who don't even read it got upset. Webtoon's statements about it reveal they are just as hypocritical, and it's honestly pathetic how hard they caved to people who don't read True Education anyways (even if they did they likely got filtered by the teacher who was a raging SJW receiving comeuppance for their actions).
I hope True Education will continue, and that it will do so soon without fully bending the knee to the outrage mob. It's a good series that while imperfect handles a lot of deep subject matter in different ways than is typically found in manga/manhwa. I'm curious how this arc will play out and if those at fault in the school will be able to learn from their mistakes and become better people, or if the coddling of others will shield them from ever having to reform their ways.
Only time will tell I guess.