If you are afraid of the cost of ethereum gas, it is better if you store ethereum on an exchange so that you are not exposed to gas fees, it is better because ethereum gas is still unstable and it is true that gas costs always fluctuate every time this really causes problems for the current ethereum blockchain users.
It is risky to store your balance on an exchange. Even though you are avoiding the cost of ethereum gas, you cannot avoid the risk of losing all your ethereum if you store it on an exchange. I think it is better to pay transaction fees or the gas instead of risking all your money.
from the case that happened in Kucoin, it seems that many people are starting to be wary of centralized exchanges,
storing crypto currency assets is better in private wallets, because the level of security is much higher, hackers cannot be prevented.
And Hey look!, Ethereum Gas on Etherscan is showing at 30 Gwei, looks like Gas has gone down, and why are you scared?
dont worry using decentralized exchanges as long as this exchanges have insurance to recover hacking case. kucoin and binance be part of exchanges that already guarantee customer fund with insurance. storing in exchanges wallet or wallet that we hold its private key have same risk.hacker have technique to attack it, remember metamask that using private key access could attacked.