I think it's fair to say that some consumptive activities are value positive, some are value neutral, and some are value negative for society as a whole. A yacht may in fact be value negative, but it doesn't mean every action where a person who holds some wealth purchases a thing to consume it is value negative.
I also disagree that the Warren Buffet statue would have a negative effect on the wealth of the average citizen. Warren Buffet would be taking capital that is locked up inside assets and spending it to build something, directly contributing significant income to the middle class (laborers) in the economy. This would have a positive beneficial effect on the economy in general.
Imagine a wealthy billionaire with all of his assets locked up in gold bars in a swiss vault. Outside of a few hired guards that protect the gold, nobody benefits. If he liquidated that gold and used the proceeds to build statues, quite a lot of people would benefit from the income generated.
If a billionaire is entombed in a safe with his symbols of wealth forever, it's as if his symbolic wealth ceases to exist. Effectively, the symbols of everybody else become more valuable to reflect the total quantity of products and services available. It's just like burning money, no wealth is destroyed, just redistributed to everybody else who holds the same currency.
Intrinsic value is not created by spending money, it's created by people doing work for that money. The right question to ask is "whom are they creating value for", not "how many papers did they get for it".
The point he is making is that they are compensated but no net value is returned to society as a result of their labor and resource expenditure. The yacht "disappears" in your private marina where it will rot away providing you with a purely private satisfaction, whereby the same labor could create houses, a public parc or some other widely shared goods, whilst still compensating the workers the same and having the same overall economic effects.
Symbolic, money wealth, thus becomes a force that diverts social physical resources away from social needs and towards private needs of wealthy individuals, making everybody else worse off compared to an alternate more egalitarian social arrangement.
I would interpret it that as long as billionaires don't sink their fortunes into megalomaniac wasteful personal consumption, like say building pyramids, the results of capitalism and inequality are not very different from a more egalitarian society, the vast majority of resources are still employed to make most people better off. What's unequal is just the representation of wealth, who owns what and who works for whom.
For example, if Warren Buffet would start to liquidate his symbolic wealth to build a giant Warren Buffet statue, this would have a net negative effect on the wealth of the average citizen. Yes, it would provide jobs, but it would also extract available capital from the market that could be invested to create other jobs, so over all it's a wash. No saleable products are generated and a massive amount of resources is required, bidding the prices of these up without putting anything back. The consumption of everybody else would diminish to accommodate for the higher prices and lower overall quantity of products now available. Society has "decided" to shift production from cars and houses towards a giant statue that nobody really needs.