They literally torpedoed Brazil and Russia's attempt at that lol.

You will need to specify what you mean by this, because I am unaware of this incident.

They dont wanna make their reserves of USD less valuable. They wont even use the USD they have to smash 3rd world debt.

This is a Chinese attitude that I myself criticized, however, it is fully understandable that the Chinese leadership is hesitant to just say fuck it and give up (on paper) $4.5T of value. That's basically 2 decades of hard earnings.

They want to maintain the stable international order.

Yeah cause having an unstable international order sucks ass. I see far too many leftists have this sort of "move fast and break things" attitude which the leadership of a country can't employ as the standard approach.

Marx explicitly says in the manifesto that a) communism is possible now (i.e. with 1848 productive forces)

In 1848 even the mathematical method for planning an economy didn't exist. If Marx ever said that a communist society could be built with 1848 levels of technology (he didn't, as in principles of communism, it was stated that it would take a long time for a newly established socialist state to "multiply the productive forces" until they were suitable for communism), then that just makes him wrong.

At best you could say that by the 1950s-1960s the technological methods became available for creating a communist society (aka numerical planning methods, convex optimisation and modern control systems theory). Even then, those are not productive forces. For much of the world, the lack of even early industrialization was a huge impediment for communism. In China, full industrialization is a relatively recent phenomenon.

The only reason for any marxist post 1848 to call for growing the productive forces is the need to develop military capabilities to defend against the imperialist cancer hellbent on destroying every ecosystem.

I'd prefer not to die from preventable diseases or coal smog or live in a world without artificial fertilizers.

There is no room tactically or theoretically for green growth.

What is your strategy? That China nukes the western populations so that they stop consuming so many resources and stop emitting so much carbon? Or that Chinese people stick to lower levels of development while the ecosystem collapses anyway from western pollution, and then the west invades the weakened China?

Even if China suddenly pulls the plug on western consumption, the only thing that causes is for the west to immediately go for WW3.

Improvements in the quality of life of who? Certainly not the people forced at gunpoint off their land by "leftist" governments to make way for mines using 760,000 litres of groundwater per second and dumping the toxic waste into their lands, waters and airs? The citydwelling labour aristocrats with legal status and formal employment see (marginal) improvements in QoL; the costs are literally dumped on the heads of the slumdwelling proletariat.

We've gone from where to where in this discussion. Which government are you talking about? How is this unspecified "leftist" government related to the discussion about China? Most capitalist global south societies have immense class distributions baked into them, I am aware of this.

However, diminishing the QoL gains from improved energy infrastructure as marginal, and those benefiting from them as labor aristocrats (even though most global south city dwellers are still heavily exploited) is just being biased and heavily subjective.

This discussion is already pointlessly long and off-topic. I ain't engaging on with the USSR stuff.