I didn't think it did, because I only apply enough pressure on the pedal to stop. Once stop I just leave my foot where it is. So I just went out and tried it your way, sure enough if you keep pressing and applying more and more pressure it bleeds to the floor. Been driving this vehicle for almost 2 years and I had never noticed this. Of course when I come to a light I always tap in neutral and pull the E-brake and take my foot of the brake pedal, so this would never happen to me anyway with my driving habits.
Like Traxy, I have now spoke with other Chevy owners. A Sonic and a 1 ton truck, both driven more than 3 years. Neither ever noticed it before. Both tried it, and by pushing on the brake pedal with a little more force after stopping, both brake pedals bled off almost to the floor. Talking with them we came up with, maybe it is a feature of the ABS system?
Maybe it is not a "feature" of the ABS system but a design flaw in the ABS. Next time the Trax needs gas (That is the only time I am allowed to drive it) I will try to remember to see if our 2018 does that. I know my 2011 Silverado does not. I have had to sit still holding a heavy load on a steep hill with the brake and it did not bleed down.