I don't agree with the word "any" here. There's nothing wrong with taking a disruptive approach to oppression when you witness it, but calculating your position relative to the system/law/culture so that you are able to live freely to act justly another day - that can be the tricky part.
I remember seeing hotel staff act in an overtly and disgustingly racist way in Cape Town, South Africa. As a tourist, hotel guest, American, and white person, I knew that I had all of the systemic privilege on my side. So I had no problem assisting the underprivileged people in that situation.
Now, with a powerful totalitarian system like China, it might be a different calculation.
If you are taking a disruptive approach to the government (at any level) of a place you are traveling, you should expect to have a high risk of getting arrested, and not necessarily being given a fair trial. If you are morally so opposed to the situation that you believe this to be a sacrifice worth making, ok then. But you shouldn't be surprised when it happens.
Also, it is not too hard to imagine a foreigner's "disruptive behavior" backfiring in terms of the impact on the locals' attitude towards the policy in question. Knowing whether or not your disruptive behavior will be a useful prod to change, or provoke a backlash against foreign meddling that actually reinforces the system in question, takes a lot of nuanced knowledge of the local society, which a foreigner will usually not have.
That's a great thing you've done in Cape Town. I remember reading Trevor Noah's book where he talks about how his father challenged Apartheid with his integrated restaurant, but ultimately got shut down by government inspectors making impossible hoops for him to jump through.
I actually still keep in touch with two of the guys who were being treated unfairly. It was a crazy situation, but not without a touch of comedy. I need to write about it sometime.
I remember seeing hotel staff act in an overtly and disgustingly racist way in Cape Town, South Africa. As a tourist, hotel guest, American, and white person, I knew that I had all of the systemic privilege on my side. So I had no problem assisting the underprivileged people in that situation.
Now, with a powerful totalitarian system like China, it might be a different calculation.