This is difficult to diagnose on a forum. I mean, someone may guess it right but, most of us are just grasping at straws(I mean that in a good way). But, we're just saying what we'd try do for ourselves.
Any of us would have to look at the brake system and see if there is one or more slider pins are sticking slightly or the rear drum brakes(many Corolla's have rear drum brakes) need a serious adjustment. OR, MAYBE IT NEEDS NOW PADS IN THE FRONT...And bleed the system.
(Here in the North), I've had sticking slider pins that still allowed the car to roll in "D" or on an incline in "N" but, made the pedal soft(travel further). IMO, Toyota's have soft brake pedals and they(Toyota/Lexus) only seems to be addressing this lately. But, if the soft pedal or pedal travel is excessive to where the vehicle barely stops(or doesn't) then, I'd need to look further just like anyone else.
1) Toyota/Lexus have a soft pedal
2) Any of the above can make it feel worse
3) IDK, I need to have a look