Seems to me that you are doing exactly what you accuse me of. You are interpreting every word in the most charitable possible light for the author and calling that the default reading. Let me break down why I think your reading is the one that imposes an assumption.

Let's start with the seemingly outlandish location. You say the author is just responding to existing social media framing, but that is exactly my point. The author chooses to further reinforce that framing, and there is nothing objective about it. It's become normalized precisely by these kinds of articles. They could have written "the station looks strange but here is the straightforward reasoning" without the word "seemingly" at all. That word preserves the "isn't this weird" tone while technically covering their bases. It is a deliberate writing choice rather than some forced interpretation.

And you didn't really address the whole "so say Chongqing Rail Transit employees" bit. If the author wanted to present the explanation as credible they would have written "Chongqing Rail Transit employees explained" or "according to" which is what you'd see in any objective reporting. The phrase "so say" has a well understood rhetorical function which is to signal skepticism. It is the same construction used in phrases like "so say the conspiracy theorists".

Then we have the hedging in the quote. You say the employee might genuinely have been that uncertain. But the point is that the article chose to end with the weakest possible version of the rationale. If the explanation is credible, why lead with the complaint and end with a maybe? That is a structural choice that prioritizes the mystery over a plain answer. The article could have opened with the plan and then noted the current lack of development. But instead the joke comes first and the serious explanation comes last with weasel words around it.

For the Manner Video clarification, you say it is for a western audience. But you haven't explained why does "a Chinese digital video production company" need a qualifier at all? The article does not describe Chongqing Morning Post as "a Chinese state affiliated newspaper" for example. That would also be just as relevant for context. Yet, one gets a label and the other does not, and the asymmetry suggests the author wants to flag the source as being potentially less authoritative.

You read "crazily dense tangle of roadways" as positive because it shows infrastructure ambition, but the word tangle has negative connotations implying messiness and lack of order. Similarly, crazily implies irrational excess. Compare that to "complex interconnected network" or "ambitious multi level design" which would've been actual unbiased framings for this. The author chose words that evoke chaos not admiration instead.

You say I am imposing bias while I am showing specific word choices and structural decisions. You are saying those choices are neutral and my reading is subjective. But language is not math and words carry tone meant to shape opinion. The author chose these words out of many possible options and that precisely where the bias lives.

You ask why not stick to clearer examples, it's because this is how real bias works. Good propaganda is intentionally written in a sophisticated enough fashion so people like you can carry water for it. It lives in the "so says" and the "seeminglys" and the asymmetric labels. It's aimed at liberals who view themselves as being sophisticated and who gobble up sophistry.