I agree w/ the "best" argument but I don't agree with the "first to market" argument.... There were a notable amount of electric cars in the UK before Tesla became a thing. Perhaps things in .de are different..
I did notice in Berlin just a few weeks ago that you guys don't really seem to be pushing for clean air zones in major cities unlike a lot of the UK which given your progressive population came as a surprise to me.
Source: https://batteryuniversity.com/article/bu-502-discharging-at-high-and-low-temperatures
I don't have any data on sodium-ion.