The difference can be explained by historical circumstance.
Whilst Europe decided to go with 220V alternating current very early on (metal filaments in incadescent bulbs became viable earlier, here), the “war of the currents (Edison with DC, Tesla with AC) dragged on in the US. As Edison introduced 100V incadescents with carbon filaments very early on, the US decided to go with 110V.
The difference in frequency (Europe has 50Hz, US 60Hz) is due to regulatory decisions.
Changing voltage means design changes on appliances, the wiring cross section and insullation should change accordingly, as well for switch, relays or other devices, the higher the voltage the more dangerous but also more efficient for transferring energy, it is a trade off and each country will like to have their standards to be accepted worldwide then it is difficult to reach an agreement because it will imply massive changes for those accepting foreign standard.