[AnarchismIsCool]

They're not faster in any absolute sense, look at the wing sweep angle of new vs old jets or the fact that early low bypass ratio jets have a much higher exhaust velocity, the old jets are marginally faster by every metric.

[WalterBright]

The airplanes can fly faster than their cruise speed. It's just not economic to do so.

[AnarchismIsCool]

Modern airplanes can exceed their cruising speed in a relative sense but older planes have a higher absolute maximum speed, as well as cruising speed.

Why is everyone trying to ackshewally this? The stat's are publicly available. Aircraft are optimized for a particular speed range and that impacts the designed cruising speed as well as Vs and VNE.