Actually, by law, some places it's more aggressive than that.Vehicles are declared a total loss when repair costs exceed the value
For example, "2/3" is often the rule. $3000 car has $2000 of damage or more, it's done. It will be given a salvage brand and then you have to rebuild it with a pretty serious and detailed inspection afterwards.
On anything more than 5 years old, a shopping cart scraping along 3 panels of paint can write the vehicle off.
There is also "unrecoverable" brands that are common, which is usually frame damage (can never be repaired). I think there's also a moderately common brand for, no parts from this vehicle can be used to repair another one, which is when it's especially compromised.
Airbags might also result in a unrecoverable or salvage brand by default in some jurisdictions, not just be a component of damage dollars.
They often don't want to give the contact info away, but there's usually a guy who works for the government that signs off on all that, (if for example, a vehicle was branded in error, or, the insurance adjuster filed the paperwork before it was agreed to be settled [happened to me], it's the guy they'll call to undo that). If you can get a hold of him and say something like "Hey, yeah it got written off for damage, but, it's just paint, it's structurally sound", they'll, very rarely, reverse the decision to brand a car. But you usually have to have proof and they have to talk to the insurance agent or whoever inspected the car. Usually there are inadequate notes (it's not the adjustor's job to help you prove this, nor the mechanics, nor was it at the time), or that person is gone or doesn't remember or whatnot. He's not the guy looking at the car, he's the industry guy doing the clerkwork, and in my case it was a person with significant clout, almost like you'd be careful how you act around a judge, even though the job is fairly mundane.