The context of the sentence to which you were responding was about motor-generated current, so it wasn't clear you were referring to friction instead.
Ok, so let's talk about friction.
Take a toughbox with CIM attached. With the motor leads unshorted, measure the breakaway torque with an appropriately-sized torque wrench. Now short the leads and repeat the same test.
If you see any difference, it's probably due to
cogging torque in the motor, not motor friction. The lion's share of the friction is in the gearbox, not the motor.
Your conclusion is correct though. A motor with high cogging torque, connected to a high-ratio gearbox, may be capable of supporting a static load.