My Honda CR/V was recalled (twice) due to software bugs that would randomly prevent the battery from charging properly. The only risk I faced was being stuck in a parking lot somewhere and having to get the car jumpstarted to get it going again. Once the car was running it ran fine. There was absolutely no safety risk, but they were formal NHTSA recalls.

If people reported this problem to the NHTSA, Honda basically could only choose whether or not to do the recall voluntarily.

Faulty rearview cameras are considered recall-worthy in the US, as they are a required safety feature for every new vehicle from May 2018 onwards.

For context, at the time of that rule being made, there were on average 210 fatalities and 15,000 injuries caused by backover crashes per year. Americans, with our love for big SUVs and trucks with terrible sight lines, basically made not having a functional backup camera into a risk for human harm.

Edit: fixed a typo

When the National Highway Traffic Safety Administration determines that a vehicle or component contains a safety defect or fails to meet a federal motor vehicle safety standard, the manufacturer is legally required to notify owners and fix the problem at no charge.

Source: https://dmvct.org/recalls-safety/how-nhtsa-safety-recalls-work/

This site states they can also be issued if the vehicle doesn’t meet a certain federal safety standard. There have also been recalls for vehicles that have been fixed OTA with a software update so a physical defect is not a requirement for a recall.