Very simplistic:

240 VAC Hot/Neutral is much more efficient than 120 VAC Hot/Neutral. Euro (residential) distribution is primarily three-wire ungrounded three-phase with varying phase-to-phase voltage. Grounding is done at the distribution transformer. Whereas North American distribution is 4-wire three-phase with single-phase 120/240 secondary distribution. Grounding in NA is done at multiple points.

Bottom line, Euro distribution allows either much more power on the same distance/size conductor, or the same amount of power to be transmitted twenty (20) times further for the same size conductor.

Again, a benefit of learning from others. Post War Europe - when power-to-the-people became the norm rather than the exception was not rich in resources. So, a system that permitted more efficient distribution became a significant advantage.

Very simplistically.

Peter Wieck
Melrose Park, PA