See the problem with the terms "intrinsic worth" and "dignity" is that they are almost meaningless and very fuzzy. What do you mean exactly?
> “All lives have equal value”
Melinda Gates repeatedly emphasized the Bill & Melinda Gates Foundation’s deep belief that all lives have equal value and everyone should be given the same chance.
I've come to the exact same conclusion that she has with harder terms. We need to give people the same chance because if done so - we are all better off.
(Edit: added "potential for the same outcome")
Applying consequentialism to ethical judgments about people is often problematic. There are various criticisms listed in [1], but they are kind of theoretical. Let me give a practical example instead. If we allow (as you say) that "protect and help the poor to make us all better off" is the best way to form a judgement about this issue because it turns out that it actually does make us all better off, then what do you do if it emerges that protecting some sub-group of the poor (say, poor people in South America) actually makes us worse off? Are they out of luck, or do you revise your judgement even though, in your terms, it was correct?
Basically, this limited world-view can instrumentalise people and is vulnerable to dangerous unforeseen consequences that lead to real human suffering.
And I'm done. Unit tests to write.
Is that an absolute? ;)
But I'm always careful with utilitarian theory - it's so easy to get wrong - if any one of your assumptions are wrong. That's why I try to make sure that the final result complies with other theories (empathy etc.).
Playing with value theories is like playing with fire.