That's right, they carry less cargo too.
Modern airplanes - say, compared to what was flying in the 80s - are actually WORSE. They are being designed with such things as efficiency, durability, ease of serviceability in mind, not with comfort or speed. The key is to get the airplane to operate with as little expense as possible because hey, these are commercial vehicles. Back in the 70s there was still a push to get people on airplanes, they don't need that anymore. So no more high frequency air circulation, comfortable seats, sexy stewardesses, and free **** cocktails in a glass.
.. my god .. Pan Am was such a dream ... i flew Rome - New York in 1987 as unaccompanied minor, smoked all the way through the flight, had two free martini (with olives), and had about as much legroom as you have today in an entire row of Easyjet.