Around a year ago, hospital treatment for Covid worldwide seems to have become noticeably more effective. Most of the world's isolation practices, China excluded, were relaxed, the rate of cases increased for several months but deaths didn't, deaths just increased steadily.
China is a couple of months into its U-turn on isolation, the number of cases is in its exponential zoom stage to infect most of the population, the big question is whether they're applying current best practice in treatment throughout the country. The lack of any statistics from the country makes it an impossible question to answer.
https://www.worldometers.info/coronavirus/ with "linear" clicked for cases and for deaths shows the road-bump from the relaxation. China's never going to produce any equivalent data.
As for the US and UK, Covid last year has officially killed around 275,000 and 50,000 respectively. Depending on your choice of measurement, the UK Covid deaths overall since the start of the pandemic vary from 200,000 to 250,000. All one can reasonably say of the US statistics is that the Covid death count is now over a million.