It's what you don't see that's significant too. Someone from Taiwan making a funny meme that might make you feel like Taiwan is a cool place that you wouldn't want something bad to happen there? Probably not going to see that. Someone in Hong Kong being nostalgic about when their vote actually made a difference? Not going to see it. A Uighur just talking about their day to day life. Not going to see it.

Everyone knows people have a limited amount of time to consume information. If they fill up that time with anything and everything other than the things they don't want you to be thinking about, they can erase these things from public consciousness.

China is full of fun and happy people! Taiwan, Hong Kong, the Uighur people? Never heard of them!

When it's a person discussing things with you rather than a very small set of algorithms controlled by a very small group of people, you'll hear about things you might not hear about from an algorithm. Sure it's determined by what the person you're talking to knows about and what they care about, so it's very random. But at there's at least there's a probability you'll hear about things that are inconvenient to the powerful people for you to know about.