Help with huge TouchPad

Or better palm detection with libinput.

My laptop has a huge touchpad (one of these incomprehensible design decisions) and it’s a regular annoyance.

According to palm detection works based among other things on exclusion zones and I think making them bigger might already help but it doesn’t seem configurable. Same for detection based on pressure.

Did I miss something? Is there any way to change this?
(I guess I could change the source and compile it myself if nothing else)