Yes, and how do you think they got to those 0 cases? Through implementing lockdowns, as they did in New Zealand, Vietnam, Singapore, Taiwan and most of Australia (it also worked in Victoria up until a state government faux pas triggered a second wave).
The likelihood of you, as an individual, catching COVID by going to your favourite bar or continued dating is low, however this virus is still contagious before any symptoms are shown. What seemed like 25 healthy people in a public space can easily turn to 5 people with COVID if one of them was unaware they were a carrier. So on, so forth.
Reintroducing social norms in a measured, staggered approach is plausible when the situation is under control, and for most countries, this is not the case. Put pessimistically, if you put the onus on the public to be more responsible and limit their activities, it will not work.
There are some exceptions, such as in Japan, but on a global scale, it's predominantly an outlier.