So far I keep my digital assets like BTC and other valuable altcoins on major exchanges like Binance and leading local exchanges. and so far the digital assets I have are safe because I use dual security or 2fa on all exchanges. but this will be very complicated if you lose your phone and your phone number is also lost.
In my opinion, storing assets on the exchange is less secure, because hacking often occurs on the exchange
Personally, for the exchange, it's usually only for trading, if it's for saving, it's more of a metamask