Just because UNESCO thinks a place is "culturally, historically, or scientifically significant" doesn't make it any less arbitrary than any other jackass' opinion
That .. is not how a World Heritage designation works.
It is the
nominating nation that declares whether a site (natural or cultural) is significant. Yes UNESCO maintains criteria of what the body considers "significant", but the nation doing the nomination understands those rules when it makes its selection. That is not hegemonic, especially since the US was the prime driver for creating the World Heritage program.