Probably when that hype on defi swaps dies down, the hackers will return back to targeting the exchange and you won't what your funds to be there when this does occur.
Some would argue that their funds are insured and in cases of hacks some of the centralized exchanges would repay the funds lost, there are however other risks involved when staking;
• The funds could lose value overtime due to supply shocks while your funds are locked up,
• Exchanges could decide to lock/seize your funds at their discretion,
• Your privacy is exposed,
Also, the insurance would depend on the extent of the back, if it renders the exchange insolvent, recovering funds would be a hassle.