Roaming charges still a mess across Europe

I just got back from a trip through three countries, and I’m still scratching my head over the charging costs. Each network has its own app, its own roaming partner list, and its own price per kWh. Sometimes the same charger costs more depending on which app you start it with. Is there no push for a unified payment system like they have with petrol pumps? I’m on a home tariff that’s cheap, but once you cross the border it feels like you’re paying whatever the local operator wants. Does anyone else find the roaming agreements and tariffs totally opaque? How do you handle it when you’re abroad? Just stick to the big networks or use