Here is a lovely old building in Camden NJ. Notice however, the Trolley car tracks! They have trains screeching by less than 15 feet from their windows!
Effective soundproofing requires a tight fit, multiple glazing layers and a large airspace. Insulated glass units rarely have even a one-inch airspace. Primary windows and storms allow 2- or 3-inch airspaces easily and unlike IG units are not mechanically connected together so the sound energy doesn’t just buzz through. The more mass you can get between you and the noise the quieter it will be. For the best soundproofing performance across the whole frequency range, you can vary glass thickness and use laminated glass to take advantage of sound reflection that occurs at every boundary