One of the things I've appreciated about living abroad is that it's helped me better understand context that I used to be swimming in. Sometimes it's context on the breadth of the human condition, but sometimes it's just my daily lesson on filter bubbles.
Google knows enough at this point to show me SCMP articles about the MTR/Cathay Pacific thing (no I'm not going to link this, because my point is precisely that maybe five people reading this know enough not to have to look it up). If it was the MTA that had banned an American Airlines ad depicting a no seriously you don't know what goes here, do you?, then I'm near-certain that it'd be all over (my) Facebook. But no, I logged in today just to check, near-certain that I wouldn't find a single mention of it. I was right.
This isn't an objective fact about the world; it's a subjective fact about who I'm talking to. Somewhere, someone has a Facebook feed full of this;