CCTV can absolutely be made to be effective and protect citizen's privacy at the same time. A legal requirement to store only encrypted data, which can only be decrypted via a court warrant (so a similar standard to searching your home or tapping your phones, not the blanket panopticon they wish to create), plus enforcement and heavy fines + prison time for anyone caught storing unencrypted data.
You need political will for this and for enforcement to take it seriously, since the technology to do so is almost trivial nowadays.
This is the kind of techno-utopian fantasy that keeps authoritarianism looking respectable. “Just encrypt it and only decrypt with a warrant” sounds lovely on paper, but in practice you’ve still built the infrastructure for a 24/7 panopticon - you’ve just wrapped it in a legal fig leaf.
Governments break their own rules all the time, warrants get rubber-stamped, and “heavy fines + prison time” magically evaporate when the offenders are the state or its contractors. The technology isn’t the hard part - it’s the fact you can’t meaningfully enforce limits on a system whose entire purpose is to watch everyone, all the time. You don’t make mass surveillance safe by adding a padlock. You stop it by not building it.
And so it's just a bill away from the data is suddenly being available for any purpose. For public safety of course. The same people who want Chat Control to scan our messages for sure want to scan and raise alarms for suspicious behaviors in public places too. They just can't implement it all at once or there'd be an uproar. But if it happens slowly like this, bit by bit... frogs getting boiled in the UK (and elsewhere too).
If you trust that the law works then the data is protected by it and there is no need for encryption. But it seems that you don't trust. Aren't you planning something illegal by chance?
You need political will for this and for enforcement to take it seriously, since the technology to do so is almost trivial nowadays.