Alas, the sentiments and provisions of the UDHR are inimical to the interests of the world's movers and shakers. They undermine the profitable racism, tribalism, nationalism and militarism so necessary to the maintenance of a parasitic, aristocratic class of "economic royalists," as FDR put it.
Cf: The 1776 American Declaration of Independence, which declared:
"We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are life, liberty and the pursuit of happiness."
For a century afterward slavery continued to be an economic mainstay -- because it was profitable to a rich, business elite. It took a civil war so shake free of it -- a process still in progress 150 years later.
Idealistic declarations are fine things, but, if inconvenient to the powerful, they're mere baubles.