You can keep those ETH in exodus, jaxx, metamask like wallets rather than in coinbase as they don't give you full access to your coins and they can froze your account anytime without prior warning.
Whenever you want to cashout your ETH, transfer it from those wallet to coinbase -> sell it -> withdraw cash to your bank account if they support your country.
I am using coinbase wallet since 2 years and using to save the money in this time period. I didn't find even single issue with the coinbase. Every wallet users really fear about they don't share the private key for their users.
Still they were under the rules accepted with the US government and running site for long time. I don't know how he uses that as the offline wallet. I think he mean to say that using vault. As of now they are supporting 4 cryptos alone. This private key issue is for all the coons wallet.