When the measure becomes the goal, it ceases to be a good measure.

The energy saving has become goal, not an efficient outcome.

Dryers can absolutely be made to be more energy efficient! They just need to use reverse-cycle airconditioners to efficiently heat the air and dehumidify it instead of simply using a resistive heater. These are much more complex to make and are expensive.

Blowing lots of cool air through clothes will also dry them eventually, which is cheap and "energy efficient". Of course, this doesn't work well in humid climates and damages clothes. It's probably overall a net loss for the environment, as making new clothes takes a lot more resources than drying them.