Actually if one looks it up (I have many times), as the Chinese industry was developing (meaning a while ago now), a large part of the key cell technology that China used came from a research group at the University of New South Wales in Australia.
There's useful research done around the world.
I think where German companies felt they might maintain a manufacturing presence was in machinery infrastructure - whether the machines that populate the factory floors that manufacture either cells of modules or machines (say, inverters) or that are used downstream of electrical production in a module.
I was last in this space some yrs ago but it's not clear to me just how much of a presence German companies have been able to keep in either.
And our building capacity got destroyed by the government, so china took over. We were on track to be number one producers, but yeah. Same is done to wind now.