Three sisters would not have gone this route and the police would likely have done nothing until after the stalking had escalated further. Also, 1 brother might not have attempted this either, especially considering the guy was a large creep and smart enough to wear a mask.
Nor would a woman allow her sisters to go vigilante for her.
These guys were quite restrained. I know families with 3 or more brothers and at least 1 sister. And for them, at best, the stalker would not be walking for awhile.
Brothers can be protective, and enraged and activated in a different way. Not saying that's the best route for this situation or others. But in many cases, it IS the best solution. Stalking can escalate very quickly.
Everyone that is like "oh they were so dumb" likely 1) doesn't understand that brother/sister dynamic, 2) hasn't had much experience with the police and/or 3) has never been violated by a stalker/home intruder/etc or very close with someone who has.
I've helped get someone arrested and charged before. I had video of the man breaking into my neighbor's car. I confronted him with my neighbor in real-time. We got him out of the car and questioned him and checked to see if anything was stolen or damaged. We called the cops, they eventually showed up after the guy left. Asked me some questions and they tried to downplay it as a likely homeless person looking for place to nap which it clearly wasn't as I saw him going through the car.
I'm talking with the cops and I see the man down the street. He never left the neighborhood. I tell the cops "there he is"! They keep asking me questions and I'm confused at their inaction. Yes he didn't take anything. But he entered the vehicle, was trespassing and going through the glovebox. Go question him!
They respond slowly and head the man's way. They do nothing. Later that night, guy comes back and is seen by the neighbor from the car incident. He sees him attempt to break into the neighbors garage. Then succeeds in breaking into the house. Cops come and take it more serious. They clear the house and arrest the guy later down the street. I submitted evidence from the earlier incident and he was charged.
Without any resolution, these criminals escalate.
It's easy to say - don't confront criminals, call the police, it's their job and they're trained. But that's what people who haven't experienced these things or had to rely on the police say.