The article explicitly accounts for the severity of different issues, and assigns them different point values.
You absolutely can reduce it to a single scalar value. You might personally disagree with the weights, but then your calculation is just a little bit different.
And you have to be able to reduce it to a scalar value at the end of the day, or else you'd never be able to make a decision about which car to buy, because you'd be entirely paralyzed when it came to cost/benefit assessments.
Technically a resolute agent can handle a utility function that messed up, but I'm not sure if people in general would be able to self-commit well enough.
You absolutely can reduce it to a single scalar value. You might personally disagree with the weights, but then your calculation is just a little bit different.
And you have to be able to reduce it to a scalar value at the end of the day, or else you'd never be able to make a decision about which car to buy, because you'd be entirely paralyzed when it came to cost/benefit assessments.