Many here are suggesting that they do not keep anything on exchanges. I doubt this. They must be having good amount on exchanges. They operate with huge amounts and must be involved in trading crypto also. It will not make much difference to their net worth even if they loose funds on one exchange due to hack. They keep the risk versus reward ratio in mind before taking such decisions. Keeping the money idle in hardware wallets or paper wallets will give them no returns at all.
The majority here are maximalists and bitcoin holders, so it is not surprising that they do not like centralized exchanges and never store assets on them. I believe what everyone says because everyone is aware of the risks of storing assets on centralized exchanges. But if someone is a day trader and says so then they are lying because no trader has enough time and money to deposit and withdraw money at the end of the day after trading.
I'm still using centralized exchanges for my P2P transactions but I'm holding my bitcoins with a hardware wallet and I don't need nor care about the small profits from staking or trading in day. Not everyone is in a hurry to make money as fast as you and take risks when staking your crypto assets on exchanges, don't impose your thoughts on others.