Ethereum has a slew of DeFi apps that are a big draw for many out of those people who wanna money which are easy to earn on the first sight but it's hard in fact. So they use those apps to add liquidity into pools,  swap their tokens, lend and borrow etc.. All those operations require a gas to pay and move fees up. There may come a time when most  of those apps  move to the side of Ethereum rivals such as Cardano etc.. then  the gas fee will inevitably go down.