ETH gas fee became high because of it's current price, the fee increases it's value as the eth price increase. Not planning to promote, but many people said that ADA(Cardano) is trying to do something to replace ETH.
Beside of it's current price there's another reason why the gas fees is high that because many people use ETH tokens to transfer from their wallet to other wallet and so on, so there's a lot transaction to process.. more people use ETH and it's token more fees we get. You can choose TRON for example to get low fees