The most salient feature of totalitarianism is control of movement, which entails tracking each citizen. Before the internet era, this could only be achieved roughly.
The state knew John Smith lived on Lumumba Street and worked on Stalin Avenue. If Smith wanted to spend a night at a woman's apartment, she had to register him at the neighborhood police station. Big Brother entered the bedroom, but not totally, for he couldn't hear all the sibilants, exhalations and squishes. Daytime movement was generally unmonitored, but the state always knew where you were at night.
Smith's ID card also prevented him from moving to the next city, much less getting a better job there, so he was stuck in Bidenstadt, his hometown.
Smith was free, though, to walk into any state store to browse, for as long as he wanted, its empty shelves.
Now, the state knows where Smith is all the time. At 5:51:15PM, this scowling man is again at Blather Bar, next to Red Levine, who, despite his name, also has alternative right tendencies. Vein-popping fans of Steve Sailer, each has left hundreds of fist-pumping comments, under "sigofnig" and "xxxxrabbi."
For the state, the whole point of tracking is to reward or punish, mostly the latter. In the past, you'd be invited to the police station, or just dragged off the street.
Now, punishment can be much tidier, and instant, even for the tiniest sin. That's where the vaccine, green, access or health passport comes in.
Comment: In just the last few months a number of Woke adverts have hit Western TV screens: in the US, a boy wearing a girl's dress being looked after by a wrathful witch baby-sitter was used to promote Twix chocolate bar; Santa being forced to show his vaccine passport to deliver children's presents was the Christmas ad for UK supermarket giant Tesco; and, yet again, a boy wearing his mother's clothes, but this time trashing his home, was used to promote John Lewis home insurance in the UK - this one was later pulled, apparently because the advertising watchdog objected to the implication that the home insurance would cover damage caused by a child who deliberately wrecked their own home: