They want 240W. 5A times 50V is 250W. It means that you can't have both voltage and current lower, you can only lower one by increasing the other. But both high

They want 240W. 5A times 50V is 250W. It means that you can't have both voltage and current lower, you can only lower one by increasing the other. But both higher voltage and higher current are a problem. More voltage will require larger clearances and better safeties (like thicker isolation on cables). "In industry, 30 volts is generally considered to be a conservative threshold value for dangerous voltage. The cautious person should regard any voltage above 30 volts as threatening, not relying on normal body resistance for protection against shock." https://iastate.pressbooks.pub/electriccircuits/chapter/chapter-1/#:~:text=In%20industry%2C%2030%20volts%20is,resistance%20for%20protection%20against%20shock https://iastate.pressbooks.pub/electriccircuits/chapter/chap.... Now, if the voltage is dangerous, it stops just being problem for the device but becomes safety hazard with all implications. On the other hand increasing current is not without problems. It quickly requires thicker cables and traces for which space is just not available in tiny USB C connector. If conductor is not thick enough the result is heating and possible melting, degrading the material over time which could lead to shorts.