This is capitalism. The goal of the Olympics is to make money on advertising, not to give nice expensive rewards to the athletes. The athletes are tools to make money for rich people. TV, advertising, sponsors.
The cheap metal serves its purpose. It looks nice initially for a few days while the winners take pictures. After that it doesn't matter.
The US Olympians used to have to pay tax on their earnings from winnings until 2016 when Obama changed that by preventing the IRS from collecting taxes on those awards.
Maybe unpopular opinion, but they should still. Why should it be tax exempt? At the end of the day, it's not enough money to worry about so it doesn't really matter. They aren't doing charity or anything though, just work that happens to be a sport and at a very high level. If we tax the rich just a tiny bit more it brings in far more tax money though, so I'd focus on that instead.