It's not an either-or. The UK has many private surveillance cameras. The UK also has many governmental entities at all levels that have undertaken specific programs to install large numbers of publicly-owned surveillance cameras. If I type "UK to install" in Google, the four autocomplete suggestions provided are all about surveillance cameras. To a first approximation, the UK isn't known for installing roads, or daycares, or traffic lights, or dictators, or shelters for the homeless, but only for surveillance cameras. Congratulations.
The UK just passed a law appointing a Surveillance Camera Commissioner to oversee all the uses of such cameras nationwide. I am not aware that any other countries have found such an appointment necessary.