Given the circumstances, definitely China. Others that did well were Vietnam and Taiwan (until the latter relaxed too much too quickly, at least). Cuba punched above its weight as usual, but still had a tough go given it's a relatively poor country.

Probably best to look at deaths per capita for countries wealthy enough to reliably be able count these deaths.

By this metric Peru did worst with 666/100k.

US at 341/100k

Canada at 135/100k

Countries widely considered by the west to have had successful control efforts are Australia 77/100k, Cringe Korea 67/100k, Japan 58/100k and New Zealand 53/100k.

Singapore had 29/100k

Venezuela had 21/100k

China at the bottom had 7/100k, down among a sea of the poorest nations in the world for whom covid tracking was a luxury.

Edit: Looking at these numbers I'm now really curious what these numbers would look like scaled against GDP. Like based on how able a country was to afford a serious response, how many people did they kill?

We cant tell yet. There has been a lot of undercounting. I know deaths in iran are atleast 2 times as much as those counted. Same with russia. And US deats reached a million in may 2021 so they are probably off by a factor of 3. Until excess deaths are properly counted and contrated with overall life expectancy trends we cant know. We have to wait a few years to plot the trends. Its hard to find exces death data. But one can look at the dip in life expectancy to get an idea. But many of the sources are not trustworthy since many of these countries have yet to report their data.

https://en.m.wikipedia.org/wiki/List_of_European_countries_by_life_expectancy

Probably China. They made preventing infection the absolute priority for about three years, which was also longer than anyone else. They had to give up when the virus became too infectious though. So I'm not sure if they are still the best. But if everyone did like China those first couple of years then we might not have COVID anymore. We'll have to see which country does best at preventing death and disability in this "giving up" phase of the pandemic.

I think first we need to establish a baseline for what constitutes "better."

Obvs USA is dead last on however you define that list.

no one has really addressed the "why" part of your question, it reminded me of this:

What we see during COVID-19 is stark operational differences between nations where politicians are the top authorities, and nations where Capital is the top authority. We are endlessly told that nations with activist governments are unfree, and that any support for these governments must come from either a pathological culture of obedience or the threat of state violence. And yet socialist nations plainly outperformed capitalist ones in terms of fighting the virus. [12]

This analysis does not imply there were simply two modes of response: capitalist and socialist. Market domination is not a binary affair, and Capital doesn’t rule by decree. As Roberts puts it, the market doesn’t tell capitalists what to do — rather, they have to guess and prognosticate and forecast and hope. Capitalists don’t find out whether they did what the market wanted until after the fact. [13] People around the world defended themselves from the virus, repressing the political will of Capital, in proportion to what they could get away with politically and economically. In socialist states, resources were deployed as deemed necessary to meet the challenge. In capitalist states in the sphere of influence of socialist China, such as South Korea, capitalists offered a decent response, perhaps because catastrophic handling would create a domestic political shift in favour of socialism. In the imperial core, where white supremacy reigns and there is no political will whatsoever to look to China for a good example, self-assured capitalists simply allowed the plague to spread essentially unopposed. In fact, imperialists succeeded to a great extent in turning the ensuing resentment into a foreign policy weapon. [14] This isn’t isolated to the most proudly capitalist nations; the kind of political power, infrastructure, and resources needed to enforce a tolerable quarantine has been completely eroded in social democratic havens like Canada and Sweden. No notable political force in the West referred to socialist successes in their efforts to affect domestic COVID-19 response policy, and I attribute this mistake to chauvinism.

from https://redsails.org/why-marxism/

Cuba went out of their way to send Drs to surrounding nations for testing and help, and then to distribute their vaccines around the Caribbean if i am correct

Most of the countries that had a major outbreak during SARS1 did well, initially, for obvious enough reasons. New Zealand also did pretty well, because public health officials took it seriously instead of going "holy shit this is infectious, way too much trouble to contain, just let the kids spread it and the lord will sort them" like a lot of other countries.

In the west only rich people will be aforded protection from ongoing and future pandemics. We could have solved most of the problem by implementing air cleaning measures in public indoor areas, and making sure everyone know the basics of wearing n95 masks when outbreaks occured, but nah. Better to just shower rich people and cops with money. Until more effective vaccines are distributed, the rest of us will just be constantly reinfected until we have a stroke, heart attack, alzheimers, or other major organ failure. But don't worry, 9 out of 10 of us will be fine enough until we get near retirement age, probably.

Funny story, we know the disease called "Spanish Flu" because that was the only honest country who didn't censor their pandemic deaths