They sure are valuable. The folks in this nomadic region of Tibet for centuries have used the jewelry and ornaments of their ceremonial costumes both as their bank accounts and as status symbols. Once or twice a year, such as at these big horse festivals, as well as on their wedding days, the men and women come out dressed in their full regalia. Many many times I have read that some women, the wives of successful traders for example, come wearing a million yuan of investments (1m yuan = 160,000 dollars = 100,000 pounds). For example in this documentary, in the scene starting from 17:30, a million yuan is quoted. And the costumes in the previous music video probably are from a special exhibition of crazy heavy/expensive costumes.

That's just the culture in the Kham region - lots of Khampas invest their wealth into jewelry and wear it all to festivals. It's a culture that goes back centuries and is still going strong. In fact, until Chinese colonisation, the rest of Tibet used to be similar, the old style of dress in Lhasa and otherplaces men and women would walk around everyday wearing a fortune (several years of their salary for instance, regardless of how high that might be), the wives of noblemen wouldn't go out without a servant in case of being robbed, and they would also sleep in their headdresses because it was considered bad luck to take it off. Their heads needed to go outside the bed.

All of this is in John Clarke's book.