How should you measure your value to the world if not by what you produce? By being very very good looking and your mother thinks you're smart? By being a nice person? Being nice should be table stakes, but ultimately, on average, people need to produce more than they consume or the world as we know it fails. It wasn't too long ago, that 50+ hours/week was a luxury - and it wasn't earned by typing at a desk.
Many contributions that people make to a functioning society can't, and never will be, quantified.
One way around this is to assign a base value to a person because they are a member of the human race and a citizen of your country, and then let them demonstrate additional value through the usual capitalist means.
It's imperfect, certainly, but it works well enough in many developed countries, and it's more accurate than the model that says what can't be measured has no value.
Models are paid to be very, very good-looking. "What you produce" is a value decision in the first place, one that society makes together by how we allocate resources.
Not what they produce, but how good they are at convincing other people to give them money. Whether it's by building a product, being very good-looking, or asking for a handout. (Sure you can say that we pay people based on what they produce if you argue that a homeless man is producing good feelings when you donate to him, but I think that's a bit silly).
Obviously this is always going to be the case to some extent in a free society, but we should definitely do more to help those who don't happen to be good at convincing other people to part with their cash.
