Consider that China is banned from the ISS and other kinds of space technology collaboration programs. China had to develop all space technology on their own. Some perspective on how significant.
It is not like even you are open all US research to one country in an instant, they would be able to build their own next decade.
China did a really good job figuring out the know-hows and had their domestic team geared up for the job. That is nothing to be dismissed, like tired 'China can't do shit without stealing our technology' circlejerks would like to indicate.
When you look at the history of space travel. One of the first space programs (NASA) originated from Germany developments. North Korea nuclear weapons from Soviet undercover collaboration. Not familiar with specifics for your claim above, but just stealing is a miniscule part of what is really required for this type of effort
In the context of for-profit business I wholeheartedly agree with you, but in the context of space exploration, if there is research about how to go to the moon and Mars that can be "stolen," isn't the moral culpability on whatever entity is hoarding that knowledge?
Or is going to the moon and Mars the achievement of certain parts of humanity, to be kept secret from other unwanted parts of humanity?
Not downplaying the achievements as they just achieved something the Soviet and Russian programs could not even at the height of their powers during the space race. But there are plenty of countries most notably Russia that have allowed China to purchase military/dual use technologies. Hardware such as advanced fighter jets, missile and rocket technology, and there’s also the huge numbers of tertiary education students who leave China for education in advanced fields before returning home for their careers. All of this will have contributed in some way to advancing China’s space flight program.
They didn’t achieve this in a vacuum, let’s not perpetuate the notion that China is isolated from the rest of the world.
Did the Soviets make any major attempt for Mars? I thought that after the moon, they were mostly focused on Venus during the space race. Their ~28 Venus missions were no joke, with up to 5300 kg payloads for lander + orbiter, comparable to the Zhurong lander + orbiter payload of 5000 kg. Perhaps someone more skilled at rocket science than me can comment on the relative difficulty of moving mass to Mars vs Venus. From the table in Wikipedia's delta-v article they look about the same.
That said, congratulations to China for this achievement, and the more rovers we have on mars, the more science we learn. I hope China also has a new space telescope on their to-do list.