I think you and the parent you're responding to agree more than you realize. They're describing the modern nation state as if totalitarianism and a Hobbesian state of nature were the only two alternatives, sprinkled with revolution. You're describing it as if the social contract was premised on mutual consent, missing the larger point that consent of the governed has historically been just a stopgap against revolution. (Really, if you believe you're in a hostage situation then revolution is the only way out).
I agree and disagree with both of you. They're right that institutional power can and does get away with trampling the social contract, to the degree it feels it can. You're right that the contract itself is (supposedly) premised on mutual consent. But both of these strike me as defeatist postures. They both have in common the idea that the contract is with the state which holds all the power. What I think you both miss is that every state and every government is just made up of people. Whatever durability liberal democracy has, or the fact that it's emerged repeatedly over a couple millenia and shown itself capable of out-producing and out-warring autocracies, is not as much premised on a Hobbesian contract or a legal contract, or even the consent of the governed, so much as it is on the consent of those in government, their own sense of social status, and the degree to which that status results from their exclusion of the people they govern or their need for approval from those people. To the extent that all these incursions on privacy are still being done in the name of protecting children or stopping terrorism, as phony as that is, it gives the people in power a psychological pass for doing what would otherwise be Stasi or KGB style intrusion. It makes them acceptable at parties and makes them able to believe that they're "the good guys". The collapse of the USSR came about because the individuals tasked with oppressing the population - from Gorbachev down to the border guards - could no longer view themselves as the good guys if they did these things to their countrymen. The last stages of an oppressive society are where fear of punishment is no longer as bad as the need to escape oppression.
For reasons that dovetail with the simplified explanations offered about what governments naturally do, etc, it's easy for a free society like Australia to slip into totalitarianism, and quite hard for it to get out. But all it really boils down to - and I mean, even down to the level of these universal observations we're all making in online comments, and up to the Congress or parliament or the inner circle of the CCP, is an individual dick measuring popularity contest. If the people in power are made to feel they are the bad guys, they'll overthrow the system. But that does require the revolution coming for its own. In this case, it will be no time at all before some MP gets entrapped by one of these things... the question on the table is really who is in charge there now and where does power flow from?