Now, Grocery Guy is incredibly brave here. I'm taking nothing away from him. That really takes incredible guts, and it probably is one of the best visual examples of standing up to authoritarian power. But you know what matters more? The response of "Tank Guy" who is driving the tank that Grocery Guy is standing up to. Here is a clip:
Tank Guy clearly has orders to go down this street. He sees a civilian in front of him. He stops, then he tries to go around him. Grocery Guy stays in front of him (again: Grocery guy is incredible). He tries again, but fails. And he refuses to murder a civilian just because those are his orders.
That is the key tipping point for toppling powerful centralized authoritarian regimes. When the enforcers decide that they will not murder civilians. As long as the enforcers are fine with going alone with killing innocent people, the only (at least potentially) viable alternative to resisting an authoritarian government is armed domestic resistance, aka, terrorism. What makes a totalitarian government fall in the face of popular resistance is the basic humanity of its enforcers who decide they no longer are willing to slaughter their fellow citizens. An example from cinema is from V for Vendetta. In the climactic scene, a host of British citizens wearing Guy Fox masks are approaching a military/security chokehold. The officer in charge frantically calls up the chain of command for orders. These orders don't come (I think because the dictator guy is dead?), so no order to kill the protesters comes. The commander orders his men to stand down. The Guy Fox masks sweep through. The Revolution Wins. The best you tube I can find follows: skip to the 1:40 mark or so.
That is when dictators fall (unless they are violently overthrown - and that rarely works out well). So praise Grocery Guy. He stood up to power in an insanely courageous manner. But Tank Guy deserves a lot of praise as well. He was unwilling to murder a fellow citizen merely for protesting. For a member of the security/army state, this is exactly what is required for (somewhat) peaceful change to happen. People note that we have no idea who Grocery Guy is, and that he may well have been "disappeared" by the Chinese State. And this is probably true. But what do you think happened to Tank Guy? He was the type of person which allows great things to happen, and he was very probably "taken care of" by the Chinese State as well. So give a prayer for Tank Guy as well.