I suspect it will be the CCS system. Although the Tesla system is nearly ideal, CCS is used by more manufacturers, as far as I know all the European and British manufacturers. It feels a bit like a replay of Beta and VHS for video recording. We had one of each over the years and even though Beta was a better system, VHS still became the standard.
I understand that even Tesla is using the CCS system in Europe. But that may be only because they anticipate that standardization (to CCS) will soon be required in Europe. It may be that the EU had some friendly advice for them.
Perhaps conversion wouldn't be a big deal. Teslas in Europe already have CCS charge ports. Most newer Teslas are CCS adapter ready. It may just be a case of retrofitting the charge port (and perhaps a bit more for older cars). So I wouldn't hold off on buying a Tesla because CCS might become the standard.
