There's a big difference between using tools intended for general population and being skilled enough in offensive security to make a difference. It may incentivise some people to learn further, but I don't think the effect would be that large. It's kind of like everyone at Uni knowing about P2P a few years ago - but they knew nothing about protocol design.

The ordinary people have their douyin/bilibili and fear of the party so they don't need to learn those things

Why would ordinary Chinese people fear the party? The party has been overseeing the greatest expansion of wealth in human history combined with a massive internal propaganda effort which I would assume is pitching them as the good guys and downplays all the brutal stuff they've done

If anything I'd expect ordinary people to be far too trusting that the authorities are reasonable and friendly. They must have real problems with earnest, motivated and well meaning people wandering off the approved parts of the internet into censored topics and getting confused by whatever happens next.

You're forgetting all the corruption and hypocrisy in China. Do you think the individuals that make up the authorities act in a "reasonable and friendly" towards regular people who interact with them? The contradictions seen by anyone who's paying attention undermine the trust you posit and some fraction of the propaganda messages.

It kinda feels like you understand China as a thought experiment and not a real place.

Fear getting disappeared/jailed for doing something forbidden. You're right that they may not see it as "fear of the party" from inside. More like "why would I do something illegal". But in a system like that those things are actually equivalent.