Donations here in the forum is still the same 10btc and 50 btc no one wants to spend that kind of amount now. The same thing would also happen for services that ignores fiat prices.
That's just a principle gesture towards the people having donated that actual number of coins. In current times based on the actual demand for Bitcoin, it should be adjusted to 0.0X BTC at most -- the more usability potential Bitcoin has, the more valuable it comes. In current times we can definitely say that there is far more usability, and that translates into items or services priced at a certain amount of coins initially, to decrease in BTC quantity value due to its increased usability based value. Explaining why something is worth exactly 0.01 or 0.1 BTC is something we in current time frame won't be able figure out. One way or another, fiat might and will likely continue to play an important role.