Yes, the brake technology has changed. Old parking brakes were typically engaged by a lever pulling a cable, and mechanically engaging parking shoes, typically in a "hat" inside the brake rotor for rear disc brake equipped vehicles that operated like old drum brakes. In cold climates, this cable could freeze or corrode over time (along with all the hardware in the "hat"), and result in the parking shoes not retracting correctly under certain conditions or as the unit aged. The basic premise on those was use it all the time or never. Binding often happened when they were used irregularly.
These explorers are equipped with electric parking brakes. There is an electric motor attached to the caliper on the rear brakes. When you pull the brake lever (or now as programmed apparently), you will hear a whirring type noise from these motors engaging the disc brake pads mechanically. Similarly, they retract when disengaged - all using the same disc brakes as used in your day to day braking. The fact it isn't a completely separate system makes it less likely to fall into disrepair from lack of use...
Me, after wrestling with all the rusted out components and frozen cables on the old mechanical systems much prefer the new electric systems....
(FWIW, my 2016 F150 has the electric parking brake and its worked flawlessly...)
