I am going to assume you have a cellar spider. Removing part of the web isn't going to directly harm them. They don't recycle their web so you aren't even removing nutrients from them.
The only way it's going to affect them is by reducing their chances of catching prey. Cellar spiders don't have a sticky web and rather rely on prey brushing up against their web, then rushing there and killing it with a bite. So you are reducing the area they are covering.
They also usually just gradually increase the size of their web. So it's unlikely it will try to rebuild everything you removed at once. Meaning it's not going to waste too much energy.
A lot of people seem to mistake carjacking for car theft. Especially mentioning that the person who shot the 13 year old was a security officer gives a wrong impression on what happened.
Carjacking is when the robber(s) take control of a car with a person inside the car. This is what happened here, with the security guard being inside the car. Under these circumstances it's perfectly reasonable to consider shooting the robbers and it's unreasonable to expect the security guard being able to identify the robber as a 13-year old harmless child. There is significant plausible risk to the person inside the car to warrent lethal force during self-defense.
Car theft is stealing an empty car. Shooting someone would be entirely unreasonable during a car theft.
The article doesn't mention wether the car had window tint and the two kids where unaware of the person inside or if they intentionally tried to rob the person. That information might change what can be considered reasonable response.