The idea of the tall bumpers was discussed here:
Because of the tolerances of the bumper zone, a robot with bumpers at the lower end of the bumper zone tolerance band colliding with a robot with bumpers at the upper end of the bumper zone tolerance band really only creates contact with about 60% of the bumper. Putting in taller bumpers that span the entire tolerance zone can increase that contact zone to 100% of the 2 noodle bumper.
As noted in that other thread, the mismatch in height of the bumpers can also lead to one robot riding up over the other robot. We have seen this in practice quite often. Putting in a 3 noodle bumper on my robot would prevent your robot from riding up on my robot (it might prevent my robot from riding up on your robot).
In addition, the taller bumper would also allow more things inside the robot to be better protected from other robot parts other than the bumper itself coming inside your frame perimeter (intakes, etc.). We have seen that a lot in practice as well.
My idea of adding additional weight allowance to the bumper weight for integrated shields that could provide additional protection is really based on the idea that if teams are faced with the choice of “spending” their weight budget on additional scoring mechanisms vs. shields, they will probably go for scoring. By including the weight budget in the bumpers, it is reserved so teams would not have the option of how to spend that budget. They could chose not to spend that budget at all (if they wanted to keep their robot lighter).