On LC+ and later Legacy, the couplers are operated using DC power. Obviously, they've licked the issue of them sticking.
FWIW, it's not that hard to run E-Units on DC, if they eventually start to stick, just jumper in AC on the coil for a few seconds, problem solved. I've installed diodes in a number of locomotives for people to quiet the E-Unit, I never got any complaints of them sticking.