Yeah, but that's because China can violate any worker rights under the Sun, and pollute as much as it wishes in the process (and producing solar cells pollutes quite a bit).

We can talk them into using less fossil fuels (probably won't work), or use incentives (which would again cost money), or we can create a by then cheap technology for getting Co2-free energy which will be stolen by everyone.

Comparing costs from climate change adaption and avoidance shows that avoidance is far cheaper - and in both cases the developed countries will have to carry the majority. (Just imagine the situation if half of Asia and Africa's harvests fail.)

The investment here is not just an economic one, it goes much further.

You close the nukes so everyone with an "Atomkraft Nein Danke" sticker on their VW votes for you.

You give huge feed in tarrif subsidy to anyone who owns a house to put panels on their roof - so the countryside votes for you.

You continue to subsidize coal so the Ruhr votes for you. But burn the coal in Poland and ship the power back - so there is no acid rain to worry about.

A perfect (if expensive) solution for everyone (unless you live east of Poland)