> For public charging DC fast chargers are incredibly expensive

Maybe so but 3 phase AC is already the minority, and we've barely started the transition to electric cars.

Look at https://www.zap-map.com/live

Orange is 3 phase AC. It's about as popular as single phase, and way less popular than DC.

They just opened a brand new transport hub near me with 100 charging points. All single phase.

I just don't think it's a big deal. I don't think people really care about the difference between 7 kW (takes hours to charge) and 22 kW (takes hours to charge).

Maybe people don't care about the hilarious clumsiness of the plug either; I don't know.