My wife’s 2012 Tahoe (5.3 V8) has begun occasionally lurching forward from a stop when light pressure is applied to the throttle. It acts as if the throttle was depressed much harder. Any ideas?

You are vehicle is fly-by-wire it could either be a problem with the sensor at the pedal or the actuator at the throttle body

First off, I would clean the throttle body. Carbon and gunk can buildup around the throttle plate restricting smooth operation. Wouldn't hurt to clean the Mass Airflow Sensor too.

Next, I would reset the idle. A scan tool will be needed for this.

Most of the time I see a lagging throttle response, but the above usually fixes the issue.

my bet is throttle body. Youtube, can of carb cleaner and a roll of blue towels.

Throttle Position Sensor on the throttle body most likely, IIRC it is a replaceable part.