Human compliance isn't perfect. Without China-level enforcement all lockdowns were leaky. There's a point of can't.

Furthermore, Covid has animal hosts. Even if the would could cooperate on completely stamping it out it would soon jump back from some animal. We simply have to live with it, take what precautions you want in your personal life but there's no point in society at large doing so.

(I do, however, think that medical facilities should be mask-required. But I think they should have been pre-pandemic, also.)