You can’t really change the default profile, because they serve as a restore point when you make mistakes in the bindings.
When you make changes to the default profile, it would ask you to duplicate into a separate profile. So any changes that you made actually saved to that new profile, not the default.
As for how it registers the input. What aircraft are you using it with? Are you on Default A320, or FlyByWire A32NX aircraft, or other generic prop aircraft.
The default profile is set to work for the sensitivity curve of the Default Asobo A320 aircraft. Meaning the curve changes depending on the area of the throttle that you move it to. Generally, the default would have an increase in sensitivity on the first half of the throttle, because you need to cover 0-85% of throttle in the cockpit to bring it from IDLE to the CLB detent. While the TCA quadrant can only cover this within 20% of range for each detent. That’s why by default the sensitivity is increased so that it can cover 85% of thrust using only 20% of movement in the quadrant. Plus it’s also designed to have reverse thrust using the same axis. Meaning the IDLE is not actually at 0% and the reverse is at negative value. Instead, the IDLE is actually at 20% thrust, while the full reverse is between 0%-20%. That’s why these are translated differently to different aircrafts. And it’s important to adjust the sensitivity curve accordingly.
When you are flying a different aircraft, let’s say a prop, or even the FBW A32NX aircraft. You need to duplicate into a separate profile specific to make it work for them. For these, you might need to adjust the sensitivity to have everything set to 0% except for the reactivity which needs to be 100%. This setting will make your throttle control to be fully linear. Meaning a 20% of change in your quadrant translates to 20% of throttle movement in the Sim. Depending on the aircrafts you’re flying, you might need to adjust different sensitivity curve.