Nothing, I trust a personal wallet more than storing crypto assets on any exchange. the collapse of FTX and Mt.Gox can be used as a lesson for anyone who still keeps their assets on the exchange.
Basically the exchange is the thing that supports this crypto industry to develop and become famous everywhere. I don't know how long it would have taken bitcoin and the entire industry to become known around the world without an exchange, but certainly exchanges are no more trusted than the wallets we control ourselves. So the crash of some famous exchanges should be a yellow light why we shouldn't trust them more than what we can afford to lose.
You can only use the exchange when making transactions, the rest is looking for a place that you can control to store the assets you have without having to involve a third party.
You can still keep some of your funds on the exchange as long as you trade with them, but don't keep your funds on the exchange as a long-term investment. Have custody for all your assets, and the best highly recommended wallet are hardware wallet. Of course, there are many other wallets that you can use to store your funds, but hardware wallets are one of the many wallets that are trusted with their level of security.