isn't using the exchanges to store your crypto kind of like storing your funds with Vanguard or Fidelity, or storing money in a bank. Of course bitcoin is not FDIC insured but I'm kind of surprised the number of people who say cold storage is the way to go.
Vanguard has SIPC insured.
Fidelity has FDIC insured.
Almost bank has FDIC insured.
BlockFi and Celsius don't have insured by FDIC or other services, they only have SAFU to protect their users (usually it's only 5-10% proportion from their profit). Many people recommended to use cold storage since in the past there's a top exchange named Mt.Gox, but this exchange suffered bankruptcy and they can't refund their customer funds. It happen on 2014, it's a good lesson why you shouldn't trust centralized services.
I think you're favor to earn some % APY on bank, to be honest it's not profitable if you calculate how much the profit you get after you subtract with fees, charges, penalties, inflation etc etc.