Staking itself has it own risk and doing so on an exchange is more riskier. With your funds on exchanges, you don't have control over your capital irrespective of how reputed that exchange is.

Chances of exchange getting hacked is high, forget that there hasn't been news of hacking occuring on exchange, this isn't because the exchanges are becoming very difficult to hack instead there are easier target now which are the so called decentralized exchanges out there with very little or no security put in place and just launched to the general public to use so they increase the value of their naive token. P

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.