I should say it's not Webtoon's fault, they're having to do their best to comply with the several (mostly) American laws that make them responsible for the type of content you output if they don't take it down. And yeah they let featured creators get away with it, because they have control over them. They can stop a featured creator to not post something line crossing, they can't stop us, so all they can do is hit with stick when they feel it's necessary.
This is another argument why you should never center your content anywhere and have multiple avenues for readers to engage with your work. Platforms are a means to an end and they have to cover their backs and we're not their friends. While there's nothing wrong with wanting them to act fairly, when they act like this we should just take note of their actions and continue to use them to pump traffic our way.