Square taper bottom brackets have been around forever...at least 40 years. A consortium of bicycle companies created the ISIS bottom bracket specifications to compete with Shimano's Octalink design. These designs added stiffness and efficiency to the bottom bracket/crank interface. Square taper cranks have an unbelievable small contact area, the newer styles contact area is about 10 times greater which increases power transfer.
Most of our bikes have transferred to hollow tech BB/cranks....even the entry level Nova.