That would do it. Although your would be incrementally pushing up the value of the remaining crypto which would be considered a bad side effect by many people.
You would need to withdraw the dollars as cash and then set fire to the bills. That would destroy them by taking them out of circulation. If you exchange them for literally anything else you want to destroy, you're just changing ownerhsip of the money, not destroying it.
Similarly, if I have some Euros, use them to buy USD banknotes, set fire to the USD banknotes, that deflates USD but not Euros. (Would that inflate Euros instead? Or deflate both?)