It's not quite the case that you get nothing for losing a wonder race. In fact, you are given an amount of gold equal to the amount of production you've sunk into the construction of the wonder until that point. It certainly isn't equally valuable, but notably, it is a far better hammer-to-gold conversion rate than "Wealth" production. It can be situationally useful.
For the record, the expansion "... his" is considered "folk etymology": a reanalysis from the Early Modern English period in the language's history. Notice for example how it doesn't make sense for feminine words: "Mary's house".
In fact, the possessive "'s" is a leftover from Old English, where the inflectional suffix "es" marked the genitive case.