A very good point about not keeping your assets in exchange it is safer when your assets are in your care and remember not your keys, not your coin, that is where plenty of people are getting it wrong, once any exchange decides to foldup then a lot of people will be left with nothing and you have to abide by these policies if you want to use their service efficiently, and holding bitcoin gives you that assurance of your assets not going anywhere, during the bear, not all coins survived it but despite everything, bitcoin is still standing strong what happened with FTX should be a lesson to many.
My friends lost 2000$ in FTX and then we become so careful with holding fund in any Cex. Before FTX i used mostly Binance to store my assets and i was thinking that Binance is secure exchange and Binance failed then whole market will crash but when FTX drama happened its give us lesson not to hold any addet in Cex you want to hold for long term. I used many times FTX exchange and fortunately when FTX ruined my ftx wallet was empty.
Now i am using Hardware to store BTC and many other altcoins. One of the biggest problem with hardware is storing new Blockchain network and it takes some time to update new network.
Holding crypto assets on exchanges is a bad idea, but we cannot deny that centralized exchanges are part of the market and are still very important to us. Without centralized exchanges, I think it would be difficult for us to invest. I don't use CEX to store bitcoins or altcoins, but I still need to use CEX to trade, as well as convert fiat, I can't find any alternative to CEX.