Aggressors[0] generally attack others one of or a combination of these reasons:

1) Pleasure/amusement/entertainment. Some people simply enjoy seeing others (everyone, specific subgroups or specific individuals) suffer.

2) Personal benefit/gain. Very often this is simply social status among peers. As aggressors grow, they refine these strategies (both consciously and unconsciously) to also gain social status in the eyes of people in positions of power (e.g. superiors/supervisors/managers), often with a resulting material benefit. Sometimes the material benefit is more direct - e.g. scammers.

A) If the punishment comes from people in positions of power:

With reason 1) it offsets the pleasure they get but quick corporal punishment is probably less effective than longer punishments such as exclusion from activities or having to perform laborious tasks.

However, with reason 2) any punishment, corporal or not, creates or reinforces a persecution complex (after all, they are just doing what they think everyone should be doing - climbing the social ladder) and often even helps them gain status because they are doing what their peers secretly also want to do - break the rules and stick it to the people in positions of power.

B) If the punishment comes from peers or especially the target, it defeats both reasons. Very few aggressors get pleasure from betting beat up by their target or other peers. And with reason 2 especially, they now risk losing social status if the target wins or it's a signal that this the behavior is not accepted by the group if it comes from peers.

The issue with B often is that to onlookers who don't know how it started, it looks like 2 people fighting, instead of one being the aggressor and the other being the target mounting a successful defense. But that can be solved through better education of people in positions of power.

What I find especially concerning are all these zero tolerance policies which actively encourage people to not defend others and sometimes even themselves.

[0]: I generally don't call them bullies because that conjures an image of children in a schoolyard but these people grow up to become adults and their behavior is driven by the same urges and incentives, it just manifests slightly differently. Being an aggressor is a mentality and a personality trait.

I wonder how hard it would be to make one of these of my town.

Surely there's publicly available lidar data that I could import into some software to slice it into squares small enough for me to 3D-print? Although I guess I'd have to make sure I'm not just printing noise where trees are...