Ethereum does not fix gas fees automatically, but gas fees will automatically decrease depending on how busy the blockchain is. If the transaction rate is higher, the gas costs will automatically be higher.
At the same time, if the price of Ethereum is high then the gas costs are also high, because the gas costs are taken from Ethereum. High because we measure in USD, if we see Ethereum issued remains the same when Ethereum price is low.
If one day the price of Ethereum is high, and the level of blockchain activity is high, then gas costs will automatically be high.