This is basically just how the PAS system on the Bafangs works.
The amperage the controller gives under PAS is defined by the settings programmed for each PAS level. There are settings for % of amps, how fast it ramps up the amps, and maximum crank speed in each assist setting, as well as some other settings.
The PAS system has no way to know how hard you're pressing on the pedal, it only knows that the pedal crank is turning, and depending on it's programming, delivers the appropriate amperage until it reaches the programmed crank speed. This is generally how hub motor controllers work with PAS as well, but the difference here is that the controller also has no idea what gear the bike is in, and therefore has no idea how much torque is being delivered to the driven wheel, nor what actual speed it's trying to attain.
I personally disabled the PAS on my BBS02, by clipping the wire that connects the pedal crank sensor to the controller. I also programmed the throttle mode to "Current" instead of "Speed" so that it doesn't behave like the PAS. Instead of a request for a given speed depending on how much throttle I apply, I request a certain amount of amperage. Small amount of throttle, small amount of amperage. Full throttle, full amps. It makes fine control at low speeds in low gears much more intuitive, and much less dangerous imho. It also makes shifting alot quicker, and easier on the drivetrain. Just keep in mind that full throttle = full amps, even if you're in top gear and not moving, and this could quite easily blow a controller up.