It's not about politeness, it's literal translation" from <--> to" languages with different systems.
Most dramas/movies are auto-translated or translated by people who are not professionals. Even VIP subscriptions in big Chinese-based corporations won't guarantee that you get human-edited lines.
Therefore, the vocabulary and sentence structure are totally off the mark. If you reverse-translate these sentences that you are talking about, you'll see that they correspond to the litteral translation.
Also, for many years, there has been a sort of unspoken agreement/custom among volunteer subtitlers (who still do 90% of the intelligible work) that subtitles will be close to the original a) to help further subtitling from English and b) to help language learners.
So, on one side you have the official channels and producers using AI, with the well-known ridiculous garbage results, and from the other side you have volunteers/underpaid humans in various websites, of various ability and aspirations, who treat subtitles either as a cultural side-dish or as fast pocket money.
In the end, all you can do is recognize the problem and then decide to consider it a part of the fun and not care about it.
