isn’t China still mostly piggybacking on foreign innovation?

I wouldn't say mostly. It happens and is a predictable thing that will happen with software and hardware. People also build their own things there. It is a very large market with multiple tech hubs, servicing itself.

They have inveated in manufacturing, Solar, Nulcear and a number of other areas to the extent where they are now world leaders. You can debate relative merits, but if you rank countries it certai ly is doomg better than most.