V5 motors have built-in PID algorithm in the firmware. You give it target position or target velocity and V5 tries to get to that position or maintain velocity. But that algorithm uses some sort of average coefficients. Also, they don’t have a way to use Inertial sensor directly.
When people talk about PID, they usually refer to implementing it themselves and tune their own coefficients for the specific robot. If they do a good job it will work more precise than the built-in algorithm and it could also use inertial sensor for turns.