This metanarrative as you decribe it is clearly false. More precisely, the idea is that humans should have equal rights and equal access to opportunities. In practice we don't even have that.
A meta-narrative doesn't require its promises to be realised physically for it to be "true" within a population. It's just a case of wether or not people "believe" it to be true.
Maybe clearly false to you, but certainly not to everyone.